The steppe eagle (''Aquila nipalensis'') is a large
bird of prey
Birds of prey or predatory birds, also known as raptors, are hypercarnivorous bird species that actively hunt and feed on other vertebrates (mainly mammals, reptiles and other smaller birds). In addition to speed and strength, these predators h ...
. Like all
eagle
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
s, it belongs to the family
Accipitridae
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-s ...
.
The steppe eagle's well-feathered legs illustrate it to be a member of the subfamily
Aquilinae
The Aquilinae are a subfamily of eagles of the family Accipitridae. The general common name used for members of this subfamily is "booted eagle", although this is also the common name of a member of the subfamily.Lerner, H., Christidis, L., Gamau ...
, also known as the "booted eagles".
[Helbig, A. J., Kocum, A., Seibold, I., & Braun, M. J. (2005). ''A multi-gene phylogeny of aquiline eagles (Aves: Accipitriformes) reveals extensive paraphyly at the genus level''. Molecular phylogenetics and evolution, 35(1), 147–164.] This species was once considered to be closely related to the
sedentary
Sedentary lifestyle is a lifestyle type, in which one is physically inactive and does little or no physical movement and or exercise. A person living a sedentary lifestyle is often sitting or lying down while engaged in an activity like soci ...
tawny eagle
The tawny eagle (''Aquila rapax'') is a large bird of prey. Like all eagles, it belongs to the family ''Accipitridae''. Its heavily feathered legs mark it as a member of the subfamily Aquilinae, also known as booted eagles.Helbig, A. J., Kocum, ...
(''Aquila rapax'') and the two forms have previously been treated as
conspecific
Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species.
Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organ ...
. They were split based on pronounced differences in morphology and anatomy;
two molecular studies, each based on a very small number of genes, indicate that the species are distinct but disagree over how closely related they are.
The steppe eagle is in many ways a peculiar species of eagle. It is a specialized predator of ground squirrel
Ground squirrels are members of the squirrel family of rodents (Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known ...
s on the breeding ground, also taking other rather small mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s and other prey, doing so more often when ground squirrels are less consistently found.[Vazhov, S. V., Bachtin, R. F., Barashkova, A. N., & Smelansky, I. E. (2013). ''On the Study of the Steppe Eagle in the Altai Kray, Russia''. Raptors Conservation, (27).] In rather treeless areas of the steppe
In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes.
Steppe biomes may include:
* the montane grasslands and shrublands biome
* the temperate grasslands, ...
habitats, these eagles tend to nest on a slightly rise, often on or near an outcrop
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth.
Features
Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial ...
, but may even the flat, wide-open ground, in a rather flat nest. They are the only eagle to nest primarily on the ground.[Brown, L. & Amadon, D. (1986) ''Eagles, Hawks and Falcons of the World''. The Wellfleet Press. .] Usually one to three eggs are laid and, in successful nests, one to two young eagles fledge.[Karyakin, I. V., Kovalenko, A. V., Levin, A. S., & Pazhenkov, A. S. (2011). ''Eagles of the Aral-Caspian Region, Kazakhstan''. Raptors Conservation, (22).] The steppe eagle undertakes a massive migration from essentially its entire breeding range, moving en masse past major migration flyways, especially those of the Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
, Red Sea
The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...
and the Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
.[ In winter, though less closely studied than during breeding, the steppe eagle is remarkable for its sluggish and almost passive feeding ecology, focusing on ]insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
swarms, landfill
A landfill site, also known as a tip, dump, rubbish dump, garbage dump, or dumping ground, is a site for the disposal of waste materials. Landfill is the oldest and most common form of waste disposal, although the systematic burial of the waste ...
s, carrion
Carrion () is the decaying flesh of dead animals, including human flesh.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
and the semi-altricial young of assorted animals, lacking the bold and predatory demeanor of their cousin species.[Steyn, P. (1983). ''Birds of prey of southern Africa: Their identification and life histories''. Croom Helm, Beckenham (UK). 1983.][Naoroji, R., & Schmitt, N. J. (2007). ''Birds of prey of the Indian subcontinent''. Om Books International.] Although still seen by the thousands at migration sites in larger numbers than other migrating eagles of these areas, the steppe eagle's entire population has declined precipitously.[Weiss, N., Haviv, E., Alon, D., Perlman, Y., & Schäckermann, J. (2019). ''How Fast Does the Steppe Eagle Population Decline? Survey Results from Eilat, Israel''. Raptors Conservation, 38.] The threats to this species consist of increasing steppe fires and pests
PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...
around the nests (both probably increased by the warming climate) which can cause a large volume of nest failures. Rivaling these factors, declines are being exacerbated by disturbance and persecution via humans, as well trampling of nests by livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals ...
. Free-flying steppe eagles are also being killed in alarmingly large numbers, especially in the stronghold nation for breeding of Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, by electrocution
Electrocution is death or severe injury caused by electric shock from electric current passing through the body. The word is derived from "electro" and "execution", but it is also used for accidental death.
The term "electrocution" was coined ...
s on dangerous electricial wires and pylons.[Karyakin, I.V. (2018). ''The status of the steppe eagle in the world: "white spots" in distribution, abundance, ecology and threats''. Raptor Research , (S1).] Due to these and other reasons, the decline of the species is thought to be considerably in excess of 50%. Therefore, the species is considered to be endangered
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...
by the IUCN
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
. The steppe eagle appears on the flag of Kazakhstan
The flag of Kazakhstan or Kazakh flag ( kk, Қазақстан туы, ; russian: Флаг Казахстана, translit=Flag Kazakhstana) was adopted on 4 June 1992, replacing the flag of the Kazakh Soviet Socialist Republic. The flag was des ...
and is the national bird of both Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
and Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
.
Taxonomy
British naturalist Brian Houghton Hodgson
Brian Houghton Hodgson (1 February 1800 or more likely 1801 – 23 May 1894) was a pioneer naturalist and ethnologist working in India and Nepal where he was a British Resident. He described numerous species of birds and mammals from the Himala ...
described the steppe eagle in 1833. ''Aquila'' is Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
for "eagle" while ''nipalensis'' means "from Nepal
Nepal (; ne, नेपाल ), formerly the Federal Democratic Republic of Nepal ( ne,
सङ्घीय लोकतान्त्रिक गणतन्त्र नेपाल ), is a landlocked country in South Asia. It is mai ...
" based on the location where the type specimen
In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...
was collected presumably while migrating.[ Samuel G. Gmelin however described a species of eagle from ]Tanais
Tanais ( el, Τάναϊς ''Tánaïs''; russian: Танаис) was an Ancient Greece, ancient Greek city in the Don River (Russia), Don river delta, called the Maeotian Swamp, Maeotian marshes in classical antiquity. It was a bishopric as Tana ...
where they were found sitting on ancient mounds or graves of nomads. He called it ''Aquila mogilnik'', the species name "mogilnik" meaning burial in Russian. This was included in the 13th edition of ''Systema Naturae'' by his cousin J.F. Gmelin in 1788. The identity of this bird was however confused with ''A. heliaca'' but research in 2019 suggests that ''A. mogilnik'' can reliably be identified and that it would have been a valid senior name for A. nipalensis had it not been declared as a ''nomen dubium,'' a doubtful name by Ernst Hartert
Ernst Johann Otto Hartert (29 October 1859 – 11 November 1933) was a widely published German ornithologist.
Life and career
Hartert was born in Hamburg, Germany on 29 October 1859. In July 1891, he married the illustrator Claudia Bernadine E ...
in 1914. The lack of usage of the name in literature now makes the name ''nomen oblitum'', a valid senior name lost by disuse. The steppe eagle is a member of the booted eagle
The booted eagle (''Hieraaetus pennatus'', also classified as ''Aquila pennata'') is a medium-sized mostly migratory bird of prey with a wide distribution in the Palearctic and southern Asia, wintering in the tropics of Africa and Asia, with a ...
subfamily within the Accipitridae
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-s ...
family.[ The booted eagle clan are ]monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...
and study of karyotype
A karyotype is the general appearance of the complete set of metaphase chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is disce ...
s has indicated that they likely have few to no close external relations within the overall extant accipitrid family.[ The booted eagle subfamily all have feathers covering their legs and may be found to some extent on every continent that contains accipitrids.][ The genus ''Aquila'' has been thought to traditionally composed of by large and fairly dark eagles that generally habituate to various open habitats. However, a significant division was determined to exist between superficially similar eagles such as the ]golden eagle
The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known bird of p ...
(''Aquila chrysaetos'') and its three extant and similar-looking close cousins, as well as three very different smaller and pale-bellied eagles (the Bonelli's, African hawk- and Cassin's hawk-eagle
Cassin's hawk-eagle (''Aquila africana'') or Cassin's eagle, is a relatively small eagle in the family Accipitridae. Its feathered legs mark it as member of the Aquilinae or booted eagle subfamily. A forest-dependent species, it occurs in primary ...
s) and the species complex
In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...
which contains the steppe eagle.[Lerner, H. R., & Mindell, D. P. (2005). ''Phylogeny of eagles, Old World vultures, and other Accipitridae based on nuclear and mitochondrial DNA''. Molecular phylogenetics and evolution, 37(2), 327–346.] There is a similar genetic disparity with the golden eagle for the steppe eagle as with the spotted eagles which have been deemed distinct enough to form a separate genus, ''Clanga''.[Väli, Ü. (2002). ''Mitochondrial pseudo‐control region in old world eagles (genus Aquila)''. Molecular Ecology, 11(10), 2189–2194.] The steppe eagle genetically clusters closely to the tawny eagle
The tawny eagle (''Aquila rapax'') is a large bird of prey. Like all eagles, it belongs to the family ''Accipitridae''. Its heavily feathered legs mark it as a member of the subfamily Aquilinae, also known as booted eagles.Helbig, A. J., Kocum, ...
as well as, albeit more distantly, with the eastern
Eastern may refer to:
Transportation
*China Eastern Airlines, a current Chinese airline based in Shanghai
*Eastern Air, former name of Zambia Skyways
*Eastern Air Lines, a defunct American airline that operated from 1926 to 1991
*Eastern Air Li ...
(''Aquila heliaca'') and Spanish imperial eagle
The Spanish imperial eagle (''Aquila adalberti''), also known as the Spanish eagle or Adalbert's eagle, is a species of eagle native to the Iberian Peninsula. The binomial commemorates Prince Adalbert of Bavaria. Due to its distinct “epaulet ...
s (''Aquila adalberti'').[Zhou, C., Tu, H., Chen, Y., Dou, L., Meng, Y., Yang, N., Yu, B. & Wu, Y. (2019). ''The complete mitochondrial genome of Aquila nipalensis and its phylogenetic position''. Mitochondrial DNA Part B, 4(2), 2152–2153.] However, the loci evidenced in the ''Aquila'' genera have been found to be relatively homogenous, with general studies of isoenzyme In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. dif ...
s showing their genes as about ten times less distanced than certain owl
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
genera.
The steppe eagle has historically been considered conspecific with the tawny eagle, even until as recently as 1991.[Amadon, D. (1982). ''The genera of booted eagles: Aquila and relatives''. Journal of the Yamashina Institute for Ornithology, 14(2–3), 108–121.] The latter species resides year-round in the African and Asian areas often used seasonally as wintering grounds by steppe eagle.[ The species were ultimately separated on the grounds of the differences in morphology, disparate coloring, distinct life histories and behaviours.][Clark, W. S. (2005). ''Steppe Eagle Aquila nipalensis is monotypic''. Bull. BOC, 125(2).] Testing of genetic materials has reinforced the species distinction of the steppe and tawny eagles. Genetically, the steppe eagle is thought to be basal to related species such as the tawny and imperial eagles.[ A fossil species, ''Aquila nipaloides'', has been found in ]Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...
, Corsica
Corsica ( , Upper , Southern ; it, Corsica; ; french: Corse ; lij, Còrsega; sc, Còssiga) is an island in the Mediterranean Sea and one of the 18 regions of France. It is the fourth-largest island in the Mediterranean and lies southeast of ...
, Sardinia
Sardinia ( ; it, Sardegna, label=Italian, Corsican and Tabarchino ; sc, Sardigna , sdc, Sardhigna; french: Sardaigne; sdn, Saldigna; ca, Sardenya, label=Algherese and Catalan) is the second-largest island in the Mediterranean Sea, after ...
and France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
and was hypothesized to most closely related to the steppe eagle based on osteology
Osteology () is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, funct ...
of the ramus Ramus can refer to:
* A branch (botany)
* A portion of a bone (from Latin ''ramus'', "branch"), as in the Ramus of the mandible or Superior pubic ramus
* A nerve ramus such as the Dorsal ramus of spinal nerve
* A taxonomic rank ("branch" in English ...
(although did evidence some differences in leg morphology).[Louchart, A., Bedetti, C., & Pavia, M. (2005). ''A new species of eagle (Aves: Accipitridae) close to the Steppe Eagle, from Pleistocene of Corsica and Sardinia, France and Italy''.] Despite being even more strongly distinctive from the steppe eagle than the tawny eagle, the eastern imperial eagle
The eastern imperial eagle (''Aquila heliaca'') is a large bird of prey that breeds in southeastern Europe and extensively through West and Central Asia. Most populations are migratory and winter in northeastern Africa, the Middle East and South ...
has been seen to hybridize
Hybridization (or hybridisation) may refer to:
*Hybridization (biology), the process of combining different varieties of organisms to create a hybrid
*Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals
*Nu ...
with the steppe eagles in the wild, once in Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
and at least three times in Kazakhstan. Each hybrid with imperial eagles has been known to involve pairs of subadult or juvenile eagles and all known hybrid pairings were between male steppe eagles (or apparent steppe-imperial hybrids themselves) mated to female imperial eagles. Some of these hybrid pairs also produced seemingly healthy young with roughly intermediate characteristics.
The steppe eagle has been generally considered to contain two subspecies. One was the nominate subspecies, ''A. n. nipalensis'', which breeds in the eastern portions of the range (perhaps from the East Kazakhstan Region
East Kazakhstan Region ( kk, Шығыс Қазақстан облысы, translit=Şyğys Qazaqstan oblysy; russian: Восточно-Казахстанская область, Vostochno-Kazakhstanskaya oblast) is a region of Kazakhstan. It occupi ...
to all points east) while the western breeding population, found in most of Kazakhstan and European Russia
European Russia (russian: Европейская Россия, russian: европейская часть России, label=none) is the western and most populated part of Russia. It is geographically situated in Europe, as opposed to the cou ...
, was considered as the subspecies, ''A. n. orientalis''. The separation of two subspecies was largely based on size, with the eastern population being larger and much heavier than the western eagles. The more eastern birds tend to be a shade darker and a have a more extensive nape patch, as well as having a more conspicuously deep gape-line.[ However, both western and Russian researchers have since made a convincing advocacy that the steppe eagle is actually a monotypical species. It was found that both previously claimed subspecies appear to broadly overlap in the breeding range and become indistinguishable at the Kazakh-Russian meeting point. The primary differences, i.e. in size and mildly in colour, can be explained as ]clinal variation
Cline may refer to:
Science
* Cline (biology), a measurable gradient in a single trait in a species across its geographical range
* Cline (hydrology), a fluid layer with a property that varies
* Cline (mathematics) or generalised circle, a circl ...
s due to the environment. The breeding populations of the eastern and western eagles are insufficiently allopatric
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...
and too extensively engage in introgression
Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Intr ...
to be properly regarded as full subspecies.[Karyakin, I., Zinevich, L., Schepetov, D., & Sorokina, S. (2016). ''The population structure of the range of the steppe eagle and preliminary data on the genetic diversity of its populations and the status of subspecies''. Feathered predators and their protection , (32).] Erroneously, a checklist once included the former subspecies of ''A. n. orientalis'' as being part of the subspecies of tawny eagle from Asia, ''A. r. vindhiana'', an error that was later corrected.
Description
The steppe eagle is a large, bulky and robust-looking eagle. It is mainly dark brown in colour with a longish but very thick neck and a relatively small head that nonetheless features a strong bill
Bill(s) may refer to:
Common meanings
* Banknote, paper cash (especially in the United States)
* Bill (law), a proposed law put before a legislature
* Invoice, commercial document issued by a seller to a buyer
* Bill, a bird or animal's beak
Plac ...
and long gape-line. It appears long-winged and has a longish and rather rounded tail and markedly well-feathered (almost with disheveled looking feathers) legs. Steppe eagles tend to perch somewhat upright and usually do so in the open, often utilizing isolated tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s, post
Post or POST commonly refers to:
*Mail, the postal system, especially in Commonwealth of Nations countries
**An Post, the Irish national postal service
**Canada Post, Canadian postal service
**Deutsche Post, German postal service
**Iraqi Post, Ira ...
s, rocks
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's ...
or other suitable low lookouts such as mound
A mound is a heaped pile of earth, gravel, sand, rocks, or debris. Most commonly, mounds are earthen formations such as hills and mountains, particularly if they appear artificial. A mound may be any rounded area of topographically higher el ...
s or straw-piles. The species often is seen on the ground where may stand for long periods of the day and walk with horizontal posture and with wingtips just exceed the tail-tip. Steppe eagles, like tawny eagles, can be relatively tame and approachable, at least compared to many of the other ''Aquila'' eagles.[ The adult is a somewhat variable brown with darker centers to the greater coverts. More pronouncedly in the eastern part of the range, adults have normally prominent pale rufous to dull orange-yellow to yellow-brown patches on the nape and hindcrown.][Dementiev, G. P., Gladkov, N. A., Ptushenko, E. S., Spangenberg, E. P., & Sudilovskaya, A. M. (1966). ''Birds of the Soviet Union, vol. 1''. Israel Program for Scientific Translations, Jerusalem.] Any other paler areas (such as the feather tips of the back and uppertail coverts) are obscured on perched adults. The massive gape-line runs to level with the rear of eye (further emphasized by dark border against paler chin) and is longer than in any other ''Aquila'' eagles including tawny eagles. Combined with their deep-set eyes, it lends steppe eagles an altogether rather fierce facial expression.[ Steppe eagle juveniles are almost invariably paler than adults, with some ranging overall from ]umber
Umber is a natural brown earth pigment that contains iron oxide and manganese oxide. In its natural form, it is called raw umber. When Calcination, calcined, the color becomes warmer and it becomes known as burnt umber.
Its name derives from '' ...
-brown to tawny-buff
Buff or BUFF may refer to:
People
* Buff (surname), a list of people
* Buff (nickname), a list of people
* Johnny Buff, ring name of American world champion boxer John Lisky (1888–1955)
* Buff Bagwell, a ring name of American professional ...
but then some are darker and more deeply brown.[Clark, W. S. (1996). ''Ageing Steppe Eagles''. Birding World, 9, 269–274.] Juveniles tend to be brown to grey-brown on the upperparts but for generally rufous-buff nape patch (more so on eastern population).[ The juveniles bear conspicuously and broadly white-tipped black about the greater coverts, wings and tail and a bold but narrow cream band on the brown medians. The juvenile steppe eagle's white uppertail coverts is generally concealed when perched; the underparts are usually the same as the upperparts but may be somewhat paler tawny-buff hue. Upon their 2nd year, the plumage is still much as the 1st year appearance but show the pale tips to secondaries, median coverts and tail as often well-worn and narrower; by the start of 2nd winter the, tips of retained juvenile flight-feathers and coverts are heavily abraded and very thin. By the end of 2nd winter, often the immatures look very worn and have nearly lost pale tips altogether and from 3rd year onward manifest a variable mix of old and new feathers. Generally, immatures are often rather scruffy in appearance until adult-like plumage attained at year five, after which the feathers generally appear more compact. Adults have brown to hazel eyes, while juveniles have distinctly dark brown eyes; the cere and feet are yellow at all ages.][
]
In flight, the steppe eagle appears as a large, impressive and visibly heavy raptor with a well-projecting large head and bill and rather broad neck and long, broad wings. They evidence proportionately long arms, especially in the larger eastern birds. The wings tend to be held almost parallel-edged and square-ended with 7 very elongated emarginations. Often juveniles can tend to appear somewhat narrower winged. The broad body of the species often looks suspended underneath and the tail appears rounded or even wedge-shaped, measuring about 3/4 of the length of wing-base. The wingspan is about 2.6 times greater than the total body length.[ On the upperwings, steppe eagles show a pale greyish primary patch that is often quite large and obvious (especially on non-adults), often being pale at the base on the greater primary coverts but on adults (especially dark birds) much less marked. On the underwing, a very small carpal crescent may be present but can vary from invisible to slightly more marked. The ]flight feather
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
s are greyish and all have 7–8 well-spaced blackish bars (albeit less conspicuously than on spotted eagles), while the fingers are plain blackish. Adults are basically all fairly uniform dark brown (wings can be negligibly greyer or rarely yellowish brown). Adults may evidence in flight some whitish patches on back and tail coverts that are varying from insignificant to fairly prominent. Adult eagles that do show a dark-barred greyish primary patch usually have that confined to a wedge-shape on inner primaries though can sometimes be rather more prominent. Below adults show dark-barred grey flight feathers and tail with the broad blackish trail edges and wing ends being rather distinctive; the wing linings are often slightly paler to darker than remiges and often with an obscure remnant of broken paler central band.[ Juveniles are quite distinctive in flight if seen in reasonable view. Above, juveniles are pale greyish-brown to yellow-brown about the body and forewing-coverts, have a broad whitish U above the tail. They possess broad white tips to the blackish greater coverts, flights feathers and tail creating obvious whitish bars on the wings and trailing edges as well as a large and prominent whitish patch covering much of the inner primaries (causing barring to stand out more so and offsetting plain black wing end). On its underside, the juvenile is mid-brown to brownish-yellow with a paler throat and creamy crissum. Below, the creamy central wing band is even broader than above, while the greater coverts all white with some dark centres on primaries (rare extreme pale individuals appear to have almost uniform paler colour on the entire wing lining and lesser and medians buffish-white to pale sandy, often whitish pale primary-wedges).][ Despite reports that some juvenile 1st years have subtle or no central wing bands, these are believed to be cases where these feathers exist but are obscured by long median coverts.][ At the end of the first year, the young steppe eagle tends to have pale tips to wings, tail and upperwing coverts become rather abraded; thereafter the development young evidence much variation due to individual differences. Usually, by the end of 2nd winter, the wing looks even more worn and uneven in pattern, with any newly acquired narrowly white-tipped quills clearly longer than old worn juvenile ones that have lost their pale tips. From the 3rd winter on, the pale parts clearly reduced, flight feathers and tail often appear quite ragged and by the 4th year start to more resemble adults. From the end of the 3rd year to when they obtain adult plumage, the eagles tend to have adult-like broad blackish trailing edges and tail often coupled with dark-barred grey base to black fingers and traces of the pale band along greater underwing-coverts.][ Maturity is obtained between the 4th and 5th years, not at 6–7 years as previously reported despite some presumed five-year-old eagles still have flecks of pale on the wing coverts and the throat and more subtle nape patches than they will ultimately manifest.][Clark, W. (2004). ''Immature Plumages of the Eastern Imperial Eagle (Aquila heliaca)''.]
Size
The steppe eagle is large and impressive raptor and quite a large eagle
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
. However, as a member of the genus ''Aquila'', it is fairly medium-sized.[''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), .] Females can range to 15% larger with greater dimorphism by weight, which is more pronouncedly dimorphic than by linear dimensions.[ Total length can range from in fully-grown steppe eagles.][Beaman, M., & Madge, S. (2010). ''The handbook of bird identification: for Europe and the western Palearctic''. A&C Black.] Wingspan in full grown eagles of this species is very variable, with the smallest steppe eagles spanning as little as while the largest ones can reportedly span up to . Although some sources list the maximum wingspan as only , the maximum wing dimensions were apparently confirmed for the most massive steppe eagles (i.e. from Altai).[Christensen, S., Nielsen, B. P., Porter, R. F., & Willis, I. (1972). ''Flight identification of European raptors''. British Birds, 64, 247–266.][Grimmett, R., Inskipp, C., Inskipp, T., & Baral, H. S. (2016). ''Birds of Nepal''. Bloomsbury Publishing.][Karyakin I.V. (2015). ''The Steppe Eagle (Aquila nipalensis)''. – Russian Raptor Research and Conservation Network.] Body mass, like wingspan, as reported is also fairly variable. Steppe eagles weighed for a Russia handbook were found to scale from in males while in females weights reported to range from .[ Elsewhere, the minimum full-grown weights for smaller western eagles (formerly subspecies ''A. n. orientalis'') were for the smallest males while the heaviest females were found to have attained a weight around , while weights in the eastern part of the breeding range are around 20% heavier.][ In one sample of steppe eagles of possibly varied origins, males weighed a mean of and females a mean of .][Kirmse, W. (1998). ''Morphometric features characterizing flight properties of palearctic eagles''. Holarctic Birds of Prey. Merida and Berlin: ADENEX and World Working Group on Birds of Prey, 339–348.] Wintering eagles of the species in southern Africa
Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of ...
weighed a mean of in a sample of four. In Saudi Arabia
Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the A ...
, 21 steppe eagles at one study site weighed a mean of while 27 eagles at another study site there weighed a mean of .[Ostrowski, S., Fromont, E., & Meyburg, B. U. (2001). ''A capture technique for wintering and migrating steppe eagles in southwestern Saudi Arabia''. Wildlife Society Bulletin, 265–268.] Unpublished weights from Israel were much lower at a reported mean of , as in other raptors during passage migration in Israel, weight loss may be significant relative to the other seasons.[Weiss, N., & Yosef, R. (2010). ''Steppe Eagle (Aquila nipalensis) Hunts a Eurasian Buzzard (Buteo buteo vulpinus) While in Migration over Eilat, Israel''. Journal of Raptor Research, 44(1), 77–78.] Steppe eagles diagnosed as from the smaller-bodied, western part of the breeding range weighed a mean of in 13 males and a mean of just under in a sample of 18 females while the mean weight of larger, eastern breeding bird was listed as in 2 males and in 2 females.[ The maximum cited weight for steppe eagle males in the wild is while that for females is .][ Among standard measurements, the wing chord can measure from in males and from in females. The ]tail
The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...
may measure from in both sexes and the tarsus may be from in males and from in females, both fairly short for the size of the eagle (although its cousin fossil speciea, ''A. nipaloides'', was apparently even shorter legged).[ Wing chord length averaged and in males and females in a study, respectively.][ The huge ]gape
The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for food, ...
of a steppe eagle is from wide, with an average of in males and females, respectively, while the gape length is , averaging in the two sexes.[ The hallux claw, the enlarged killing talon on the rear foot of essentially all ]accipitrid
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-s ...
s measures from , averaging , in males from , averaging , in females. As in the tawny eagle and imperial eagles, the talon size is modest, whereas most species in the golden eagle clade are markedly larger clawed relative to their size.[
]
Confusion species
In many circumstances, the steppe eagle can be very difficult to distinguish from other similar eagles, often especially during passage and winter.[ Adults are often confused with spotted eagles but are best separated by their much more broad build, far greater wing areas with longer, more rectangular or squarish wing tips and longer, more conspicuous fingers, larger head (rather than small and bull-headed) and larger overall size.][Forsman, D. (1999). ''The raptors of Europe and the Middle East: a handbook of field identification''. London: T & AD Poyser.] Compared to the spotted eagles, the flight of the steppe eagle is more aquiline, i.e. more powerful, labored and deep while spotted eagles tend to fly more like buzzards
Buzzard is the common name of several species of birds of prey.
''Buteo'' species
* Archer's buzzard (''Buteo archeri'')
* Augur buzzard (''Buteo augur'')
* Broad-winged hawk (''Buteo platypterus'')
* Common buzzard (''Buteo buteo'')
* Eastern b ...
.[ The ]lesser spotted eagle
The lesser spotted eagle (''Clanga pomarina'') is a large Eastern European bird of prey. Like all typical eagles, it belongs to the family Accipitridae. The typical eagles are often united with the buteos, sea eagles, and other more heavy-set Acc ...
(''Clanga pomarina''), the most similarly marked of spotted eagles, is particularly less powerful looking with a shorter neck, much smaller wing areas, shorter fingers and tail and less extensive, baggy leg-feathering. The greater spotted eagle
The greater spotted eagle (''Clanga clanga''), occasionally called the spotted eagle, is a large bird of prey. Like all typical eagles, it belongs to the family Accipitridae. Its feathered legs indicate it is a member of the subfamily Aquilinae ...
(''Clanga clanga'') is also smaller and slighter but to a reduced extent. When plumage is clear to see, steppe eagles have more clearly and more extensively barred quills and lack the clear carpal arcs of the two widespread spotted eagles but these differences are obscured at greater distances. Some subadult steppe eagles, with their paler brown wing-coverts above and below and only traces of white underwing bands and clearly pale primary patch above in particular quite resemble the plumage of older lesser spotted eagles. The white wing bars of steppe eagles are usually more conspicuous than those of the lesser spotted eagle.[Forsman, D. (1991). ''Die Bestimmung von Schell-Aquila clanga, Schrei-A. pomarina und Steppenadler A. nipalensis''. Limicola, 5, 145–185.][Alexander, H. G. (1952). ''Identifying birds of prey in the field'', 72: 55–61.] At close range, the steppe eagle has a deeper gape than lesser and greater spotted eagles and has rounded rather than oval nostrils.[ When seen perched, either on a perch or on the ground, spotted eagles of all three species tend to stand quite tall and upright, emphasizing their more slender and lightly feathered legs, while the steppe eagle sits more horizontally and is always far bulkier than even the biggest greater spotted eagles.][ Some particularly dark adult and subadult steppe eagles with obscured paler wing feathers can greatly resemble adult greater spotted eagles (the latter species can appear almost blackish in certain lights) and would need to be identified by the differences in size and form.][ The ]Indian spotted eagle
The Indian spotted eagle (''Clanga hastata'') is a large bird of prey native to South Asia. Like all typical eagles, it belongs to the family Accipitridae. The typical eagles are often united with the buteos, sea eagles and other more heavyset Ac ...
(''Clanga hastata'') has a deep gape reminiscent of the steppe eagle but is much slighter in overall size, being similar in size or even smaller than a lesser spotted eagle, and has even less conspicuous whitish wing markings than the lesser spotted.[ As a result of their rough similarities, many young steppe eagles are misidentified, particularly from a distance, with spotted eagles although generally, identification is possible via a combination of structure and plumage features.][ Juvenile steppe eagles are normally readily identified by distinctive plumage features but can recall juvenile ]eastern imperial eagle
The eastern imperial eagle (''Aquila heliaca'') is a large bird of prey that breeds in southeastern Europe and extensively through West and Central Asia. Most populations are migratory and winter in northeastern Africa, the Middle East and South ...
s, the latter has a longer and less rounded tail, a more prominent (rather than deeply set) bill, has a much paler and more buff overall colour while the chest is overlaid with brown streaking and the quills are unbarred. Imperial and steppe eagles are often similar in size, with more western breeding birds usually being somewhat smaller when seen side by side with an imperial eagle and the eastern steppe eagles being of similar average size (but even larger maximum size) compared to full-grown imperial eagles.[ Steppe eagles are told from ]tawny eagle
The tawny eagle (''Aquila rapax'') is a large bird of prey. Like all eagles, it belongs to the family ''Accipitridae''. Its heavily feathered legs mark it as a member of the subfamily Aquilinae, also known as booted eagles.Helbig, A. J., Kocum, ...
s by that species being smaller and less bulky with shorter wings, a smaller gape, a more slender neck and a relatively longer tail. Both the tawny and steppe eagle tend to have a distinct S-shape curvature to the trailing edge of the wings. When perched on the ground, the tawny eagle tends to stand more upright, while the steppe eagle often appears to assume a more elongated, horizontal posture. Plumage variations of tawny eagles can render them a surprisingly close colour to the usually darker, duller and browner steppe eagle (especially so in south Asia
South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...
), but they never obtain the distinct whitish wing band of the young steppe eagle nor the nape patch of most adult steppes.[ Despite slight individual and clinal variations, the steppe eagle, unlike the tawny eagle, is not polymorphic.][ These aforementioned eagles present the main possibilities for confusion, less likely mistakes can potentially range from relatively dainty and much smaller ]Wahlberg's eagle
Wahlberg's eagle (''Hieraaetus wahlbergi'') is a bird of prey that is native to sub-Saharan Africa, where it is a seasonal migrant in the woodlands and savannas.
It is named after the Swedish naturalist Johan August Wahlberg. Like all eagles, it ...
s (''Hieraeetus wahlbergi'') (generally quite different in features but somewhat similarly hued) in Africa to the somewhat bigger but differently structured golden eagle
The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known bird of p ...
s (much longer tail, relatively smaller bill and much smaller gape, different wing shape, more aquiline build and bigger feet and talons) in much of the range.[
]
Range and habitat
Breeding and wintering ranges
Although the breeding range is rather extensive, the steppe eagle is essentially confined to nesting in only four large nations: Russia
Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
, Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
and China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
. However, the steppe eagle once bred in Europe. Here, they bred into the 20th century in at least southeasternmost Ukraine
Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...
and perhaps elsewhere in eastern Europe
Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural, and socio-economic connotations. The vast majority of the region is covered by Russ ...
. These eagles still rarely occur as breeders in southwest Russia from Stavropol
Stavropol (; rus, Ставрополь, p=ˈstavrəpəlʲ) is a city and the administrative centre of Stavropol Krai, Russia. As of the 2021 Census, its population was 547,820, making it one of Russia's fastest growing cities.
It was known as ...
to Astrakhan
Astrakhan ( rus, Астрахань, p=ˈastrəxənʲ) is the largest city and administrative centre of Astrakhan Oblast in Southern Russia. The city lies on two banks of the Volga, in the upper part of the Volga Delta, on eleven islands of the ...
.[ The steppe eagle is still mapped to breed down to ]Makhachkala
Makhachkala ( rus, Махачкала, , məxətɕkɐˈla, links=yes),; av, Махӏачхъала, Maħaçqala; ce, ХӀинжа-ГӀала, Hinƶa-Ġala; az, Маһачгала, Mahaçqala; nog, Махачкала; lbe, Махачкъала; ...
and Maykop
Maykop (russian: Майкоп, p=mɐjˈkop Help:IPA/Russian, mɐj'kop); ady, Мыекъуапэ, Mıéquapə ) is the capital city of the Republic of Adygea in Russia, located on the right bank of the Belaya River (Kuban), Belaya River (a tribut ...
to as far west as Leningradskaya, up north as far as the lower Volga
The Volga Region (russian: Поволжье, ''Povolzhye'', literally: "along the Volga") is a historical region in Russia that encompasses the drainage basin of the Volga River, the longest river in Europe, in central and southern European Rus ...
and down to the Caspian Sea
The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...
nearly as far as Makhachkala
Makhachkala ( rus, Махачкала, , məxətɕkɐˈla, links=yes),; av, Махӏачхъала, Maħaçqala; ce, ХӀинжа-ГӀала, Hinƶa-Ġala; az, Маһачгала, Mahaçqala; nog, Махачкала; lbe, Махачкъала; ...
and south of Fort-Shevchenko
Fort-Shevchenko ( kk, Форт-Шевченко) is a military-base town and administrative centre of Tupkaragan District in Mangystau Region of Kazakhstan on the eastern shore of Caspian Sea. Primary industries include fishing and the extract ...
. The breeding range extends through appropriate habitat in much of Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, from north of Nur-Sultan
Astana, previously known as Akmolinsk, Tselinograd, Akmola, and most recently Nur-Sultan, is the capital city of Kazakhstan.
The city lies on the banks of the Ishim (river), Ishim River in the north-central part of Kazakhstan, within the Akmo ...
south to (albeit spottily) to Kyzylorda
Kyzylorda ( kk, Қызылорда, translit=Qyzylorda, ), formerly known as Kzyl-Orda (russian: Кзыл-Орда), Ak-Mechet (Ак-Мечеть), Perovsk (Перовск), and Fort-Perovsky (Форт-Перовский), is a city in south-cen ...
as well as around the former Aral Sea
The Aral Sea ( ; kk, Арал теңізі, Aral teñızı; uz, Орол денгизи, Orol dengizi; kaa, Арал теңизи, Aral teńizi; russian: Аральское море, Aral'skoye more) was an endorheic basin, endorheic lake lyi ...
. From their main breeding areas to the north, steppe eagles breed also marginally in northeastern Kyrgyzstan
Kyrgyzstan,, pronounced or the Kyrgyz Republic, is a landlocked country in Central Asia. Kyrgyzstan is bordered by Kazakhstan to the north, Uzbekistan to the west, Tajikistan to the south, and the People's Republic of China to the east. ...
and perhaps northern Uzbekistan
Uzbekistan (, ; uz, Ozbekiston, italic=yes / , ; russian: Узбекистан), officially the Republic of Uzbekistan ( uz, Ozbekiston Respublikasi, italic=yes / ; russian: Республика Узбекистан), is a doubly landlocked cou ...
. The breeding distribution is essentially continuous as sweep far to the east in Russia as Transbaikal
Transbaikal, Trans-Baikal, Transbaikalia ( rus, Забайка́лье, r=Zabaykalye, p=zəbɐjˈkalʲjɪ), or Dauria (, ''Dauriya'') is a mountainous region to the east of or "beyond" (trans-) Lake Baikal in Far Eastern Russia.
The steppe and ...
and Altai. The steppe eagle also breeds in large stretches of western and northern China such as Tian Shan
The Tian Shan,, , otk, 𐰴𐰣 𐱅𐰭𐰼𐰃, , tr, Tanrı Dağı, mn, Тэнгэр уул, , ug, تەڭرىتاغ, , , kk, Тәңіртауы / Алатау, , , ky, Теңир-Тоо / Ала-Тоо, , , uz, Tyan-Shan / Tangritog‘ ...
, Xinjiang
Xinjiang, SASM/GNC: ''Xinjang''; zh, c=, p=Xīnjiāng; formerly romanized as Sinkiang (, ), officially the Xinjiang Uygur Autonomous Region (XUAR), is an autonomous region of the People's Republic of China (PRC), located in the northwest ...
, the Gobi area, Gansu
Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province.
The seventh-largest administrative district by area at , Gansu lies between the Tibet ...
, Ningxia
Ningxia (,; , ; alternately romanized as Ninghsia), officially the Ningxia Hui Autonomous Region (NHAR), is an autonomous region in the northwest of the People's Republic of China. Formerly a province, Ningxia was incorporated into Gansu in ...
, northern Tibet
Tibet (; ''Böd''; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa people, ...
(by far their southernmost breeding area), Inner Mongolia
Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an autonomous region of the People's Republic of China. Its border includes most of the length of China's border with the country of Mongolia. Inner Mongolia also accounts for a ...
and reach their eastern breeding limits in Manchuria
Manchuria is an exonym (derived from the endo demonym " Manchu") for a historical and geographic region in Northeast Asia encompassing the entirety of present-day Northeast China (Inner Manchuria) and parts of the Russian Far East (Outer Manc ...
and elsewhere in northeastern China
Northeast China or Northeastern China () is a geographical region of China, which is often referred to as "Manchuria" or "Inner Manchuria" by surrounding countries and the West. It usually corresponds specifically to the three provinces east of t ...
. The species breeding range is also quite broad into Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
excluding the northern portion. The steppe eagle is entirely migratory, wintering in east
East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth.
Etymology
As in other languages, the word is formed from the fa ...
and, to a lesser extent, southern Africa
Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of ...
. Their African range can extend western to southern Sudan
Sudan ( or ; ar, السودان, as-Sūdān, officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It shares borders with the Central African Republic t ...
, almost throughout east Africa
East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa:
Due to the historical ...
, to the easternmost part of Democratic Republic of the Congo
The Democratic Republic of the Congo (french: République démocratique du Congo (RDC), colloquially "La RDC" ), informally Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly and also colloquially Zaire, is a country in ...
.[ The southern African wintering range extends to central ]Angola
, national_anthem = " Angola Avante"()
, image_map =
, map_caption =
, capital = Luanda
, religion =
, religion_year = 2020
, religion_ref =
, coordina ...
, northern and eastern Namibia
Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...
south to Botswana
Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label=Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalahar ...
, Zambia
Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most cent ...
, Zimbabwe
Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and Mozam ...
, Eswatini
Eswatini ( ; ss, eSwatini ), officially the Kingdom of Eswatini and formerly named Swaziland ( ; officially renamed in 2018), is a landlocked country in Southern Africa. It is bordered by Mozambique to its northeast and South Africa to its no ...
and northern South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
, including former Transvaal Transvaal is a historical geographic term associated with land north of (''i.e.'', beyond) the Vaal River in South Africa. A number of states and administrative divisions have carried the name Transvaal.
* South African Republic (1856–1902; af, ...
and northern Natal
NATAL or Natal may refer to:
Places
* Natal, Rio Grande do Norte, a city in Brazil
* Natal, South Africa (disambiguation), a region in South Africa
** Natalia Republic, a former country (1839–1843)
** Colony of Natal, a former British colony ( ...
as well as rarely south of the Orange River
The Orange River (from Afrikaans/Dutch: ''Oranjerivier'') is a river in Southern Africa. It is the longest river in South Africa. With a total length of , the Orange River Basin extends from Lesotho into South Africa and Namibia to the north ...
[Dowsett, R. J., Aspinwall, D. R., & Dowsett-Lemaire, F. (2008). ''The birds of Zambia: an atlas and handbook''. Tauraco Press.][Irwin, M. P. S. (1981). ''The birds of Zimbabwe''. Quest Pub.] In South Africa, steppe eagles are reportedly often frequent only in the lowveld
Veld ( or ), also spelled veldt, is a type of wide open rural landscape in :Southern Africa. Particularly, it is a flat area covered in grass or low scrub, especially in the countries of South Africa, Lesotho, Eswatini, Zimbabwe and Botswa ...
of Kruger National Park
Kruger National Park is a South African National Park and one of the largest game reserves in Africa. It covers an area of in the provinces of Limpopo and Mpumalanga in northeastern South Africa, and extends from north to south and from ea ...
area. The steppe eagle's wintering range also extends into the Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
. They occur broadly in the season in several central and southern parts of the Arabian Peninsula
The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...
as well as regularly in eastern Iraq
Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
and western Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
with odd ones north to Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
and Georgia
Georgia most commonly refers to:
* Georgia (country), a country in the Caucasus region of Eurasia
* Georgia (U.S. state), a state in the Southeast United States
Georgia may also refer to:
Places
Historical states and entities
* Related to the ...
.[Al-Sheikhly, O. F., Al-Barazangi, A. N., Haba, M. K., Fazaa, N. A., Abdulzahra, H. K., Turab, M. K. A., & Al-Azawi, A. J. (2017). ''Ring Recoveries from Steppe Eagles and Eastern Imperial Eagles from the Russian and Kazakhstan Breeding Populations and a Review of Major Threats to Eagles in Iraq''. Raptors Conservation, 35.][Abuladze, A. (2013). ''Birds of prey of Georgia''. Materials Towards a Fauna of Georgia, Issue VI. Ilia State University, Institute of Zoology, Tbilisi.] Although sometimes recorded as occurring "somewhat" in Arabia, more extensive surveying has revealed that many, if not more, steppe eagles wind up winter in the peninsula rather than Africa, and that the largest ever winter numbers were recorded in Saudi Arabia
Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the A ...
, where around 7200 individuals (or perhaps up to 9% of the current world population) were recorded near Riyadh
Riyadh (, ar, الرياض, 'ar-Riyāḍ, lit.: 'The Gardens' Najdi pronunciation: ), formerly known as Hajr al-Yamamah, is the capital and largest city of Saudi Arabia. It is also the capital of the Riyadh Province and the centre of the R ...
.[Keijmel, M., Babbington, J., Roberts, P., McGrady, M. & Meyburg, B. U. (2020). ''The world's largest gathering of Steppe Eagles Aquila nipalensis discovered in central Saudi Arabia''. Sandgrouse, 42: 59–68.] As many as 3000 have also been similarly recorded in the nation of Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of t ...
.[ Other nations to host wintering steppe eagles include ]Yemen
Yemen (; ar, ٱلْيَمَن, al-Yaman), officially the Republic of Yemen,, ) is a country in Western Asia. It is situated on the southern end of the Arabian Peninsula, and borders Saudi Arabia to the Saudi Arabia–Yemen border, north and ...
, Azerbaijan
Azerbaijan (, ; az, Azərbaycan ), officially the Republic of Azerbaijan, , also sometimes officially called the Azerbaijan Republic is a transcontinental country located at the boundary of Eastern Europe and Western Asia. It is a part of th ...
and Syria
Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...
as well as, albeit rarely doing so, in the United Arab Emirates
The United Arab Emirates (UAE; ar, اَلْإِمَارَات الْعَرَبِيَة الْمُتَحِدَة ), or simply the Emirates ( ar, الِْإمَارَات ), is a country in Western Asia (The Middle East). It is located at th ...
, Lebanon
Lebanon ( , ar, لُبْنَان, translit=lubnān, ), officially the Republic of Lebanon () or the Lebanese Republic, is a country in Western Asia. It is located between Syria to the north and east and Israel to the south, while Cyprus li ...
and Kuwait
Kuwait (; ar, الكويت ', or ), officially the State of Kuwait ( ar, دولة الكويت '), is a country in Western Asia. It is situated in the northern edge of Eastern Arabia at the tip of the Persian Gulf, bordering Iraq to the nort ...
.
Unusually, a few overwintering steppe eagles have been now recorded in Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, apparently near Shymkent
Shymkent (; Шымкент, Şymkent), known until 1993 as Chimkent ( uz, Çımkent, چىمكېنت; Yañalif: Çimkent ()); russian: Чимкент, translit=Chimkent (), is a city in Kazakhstan. It is near the border with Uzbekistan. It is one ...
, in the Aksu-Zhabagly Nature Reserve, the valley of the Syr Darya
The Syr Darya (, ),, , ; rus, Сырдарья́, Syrdarjja, p=sɨrdɐˈrʲja; fa, سيردريا, Sirdaryâ; tg, Сирдарё, Sirdaryo; tr, Seyhun, Siri Derya; ar, سيحون, Seyḥūn; uz, Sirdaryo, script-Latn/. historically known ...
, the Chardara Dam
The Chardara Dam ( kk, Shardara), also known as Chardarin Dam, is an earth-fill embankment dam on the Syr Darya River in Shardara District, Kazakhstan. It was constructed between 1964 and 1968 with the primary purpose of irrigation. The dam has a ...
and towns of the East Kazakhstan Region
East Kazakhstan Region ( kk, Шығыс Қазақстан облысы, translit=Şyğys Qazaqstan oblysy; russian: Восточно-Казахстанская область, Vostochno-Kazakhstanskaya oblast) is a region of Kazakhstan. It occupi ...
.[Gennadievich, K. V. (2006). ''Winter meetings of the Steppe Eagle Aquila nipalensis in southern Kazakhstan''. Russian Ornithological Journal, 1208: 3923.][Nikolaevich, B. N. & Petrovna, R. I. (2020). ''Winter observations of the Aquila nipalensis Steppe eagle in the Bukhtarminsk Valley in South Altai''. Russian Ornithological Journal, 1871: 38–40.] In south Asia
South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...
, the species in winter may occur from Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
(rarely wintering still in the Nuristan Province
Nuristan, also spelled as Nurestan or Nooristan (Dari: ; Kamkata-vari: ), is one of the 34 provinces of Afghanistan, located in the eastern part of the country. It is divided into seven districts and is Afghanistan's least populous province, wi ...
) and in much of the Indian subcontinent
The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...
.[ ]Pakistan
Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
's Poonch Poonch, sometimes also spelt Punchh, may refer to:
* Historical Poonch District, a district in the princely state of Jammu and Kashmir in British India, split in 1947 between:
** Poonch district, India
** Poonch Division, in Azad Kashmir, Pakistan, ...
and Jhelum valleys of Azad Kashmir
Azad Jammu and Kashmir (; ), abbreviated as AJK and colloquially referred to as simply Azad Kashmir, is a region administered by Pakistan as a nominally self-governing entitySee:
*
*
* and constituting the western portion of the larger Ka ...
are known to host a mean of 154 steppe eagles per study area. In India, they may occur mainly south to Madhya Pradesh
Madhya Pradesh (, ; meaning 'central province') is a state in central India. Its capital is Bhopal, and the largest city is Indore, with Jabalpur, Ujjain, Gwalior, Sagar, and Rewa being the other major cities. Madhya Pradesh is the seco ...
, the Indo-Gangetic Plain
The Indo-Gangetic Plain, also known as the North Indian River Plain, is a fertile plain encompassing northern regions of the Indian subcontinent, including most of northern and eastern India, around half of Pakistan, virtually all of Bangla ...
, the Deccan Peninsula and Himalayan zone, Mizoram
Mizoram () is a state in Northeast India, with Aizawl as its seat of government and capital city. The name of the state is derived from "Mizo people, Mizo", the endonym, self-described name of the native inhabitants, and "Ram", which in the Mizo ...
, Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
and southern Orissa
Odisha (English: , ), formerly Orissa ( the official name until 2011), is an Indian state located in Eastern India. It is the 8th largest state by area, and the 11th largest by population. The state has the third largest population of Sch ...
.[Sashi Kumar, C. (2004). ''Aquila eagles in Kerala, India''. News Ornis, 1(4), 53–54.] Vagrants have been recorded in India to Periyar National Park
Periyar National Park and Wildlife Sanctuary (PNP) is a protected area located in the districts of Idukki and Pathanamthitta in Kerala, India. It is notable as an elephant reserve and a tiger reserve. The protected area encompasses , of which ...
, Mahendragiri, Kanyakumari Wildlife Sanctuary
Kanyakumari Wildlife Sanctuary is a protected area in Kanyakumari district, Tamil Nadu South India declared in February 2008. The area is a tiger habitat. Seven rivers originate in the forest including the Thamirabarani River and Pahrali River ...
and Mudumalai National Park
Mudumalai National Park is a national park in the Nilgiri Mountains in Tamil Nadu, south India. It covers at an elevation range of in the Nilgiri District and shares boundaries with the states of Karnataka and Kerala. A part of this area has ...
.[ The wintering range extends east to ]Tibet
Tibet (; ''Böd''; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa people, ...
(although the species is said to be gone from Lhasa
Lhasa (; Lhasa dialect: ; bo, text=ལྷ་ས, translation=Place of Gods) is the urban center of the prefecture-level city, prefecture-level Lhasa (prefecture-level city), Lhasa City and the administrative capital of Tibet Autonomous Regio ...
in recent years), Nepal
Nepal (; ne, नेपाल ), formerly the Federal Democratic Republic of Nepal ( ne,
सङ्घीय लोकतान्त्रिक गणतन्त्र नेपाल ), is a landlocked country in South Asia. It is mai ...
, Burma
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...
and broadly in east China
East China () is a geographical and a loosely defined cultural region that covers the eastern coastal area of China.
A concept abolished in 1978, for economical purposes the region was defined from 1949 to 1961 by the Chinese Central Governme ...
from southeastern Guizhou
Guizhou (; formerly Kweichow) is a landlocked province in the southwest region of the People's Republic of China. Its capital and largest city is Guiyang, in the center of the province. Guizhou borders the autonomous region of Guangxi to t ...
to Hainan
Hainan (, ; ) is the smallest and southernmost province of the People's Republic of China (PRC), consisting of various islands in the South China Sea. , the largest and most populous island in China,The island of Taiwan, which is slightly l ...
and southwestern Guangdong
Guangdong (, ), alternatively romanized as Canton or Kwangtung, is a coastal province in South China on the north shore of the South China Sea. The capital of the province is Guangzhou. With a population of 126.01 million (as of 2020) ...
.[ Recent wintering records reflect the species as lingering seasonally at different points of the non-breeding season, albeit very seldom, in central and southern ]Myanmar
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...
, western Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...
, peninsular Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
and northern Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
.[Duckworth, J. W., Inskipp, T. P., Pasquet, E., Rasmussen, P. C., Rice, N. H., Robson, C. R., & Russell, D. G. D. (2008). ''A re-evaluation of the status of Tawny Eagle Aquila rapax in South-East Asia''.] The species may have been aided in expanding their eastward wintering range by deforestation
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated d ...
practice.
Migratory range
The steppe eagle appears broadly in many nations between their central Eurasian breeding areas and their generally tropical Indo and African wintering grounds. As a matter of fact, the largest concentrations of the species tend to occur at times of passage.[ The steppe eagle can also vagrate not infrequently far away from traditional migration sites, and has turned up in many areas from ]western Europe
Western Europe is the western region of Europe. The region's countries and territories vary depending on context.
The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the ancient Mediterranean ...
to as far east as Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
. Vagrant steppe eagles have been recorded in at least the following nations or regions: at least 6 nations in west Africa
West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Maurit ...
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...
, Tunisia
)
, image_map = Tunisia location (orthographic projection).svg
, map_caption = Location of Tunisia in northern Africa
, image_map2 =
, capital = Tunis
, largest_city = capital
, ...
, the Netherlands
)
, anthem = ( en, "William of Nassau")
, image_map =
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of the Netherlands
, established_title = Before independence
, established_date = Spanish Netherl ...
, Finland
Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...
(at least 50 times) as well as Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, i ...
and France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
, the Czech Republic
The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...
, Bulgaria
Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedon ...
and Romania
Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...
(in both of which they once bred but were extirpated), Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with ...
Mordovia
The Republic of Mordovia (russian: Респу́блика Мордо́вия, r=Respublika Mordoviya, p=rʲɪsˈpublʲɪkə mɐrˈdovʲɪjə; mdf, Мордовия Республиксь, ''Mordovija Respublikś''; myv, Мордовия Рес ...
, Yakutia
Sakha, officially the Republic of Sakha (Yakutia),, is the largest republic of Russia, located in the Russian Far East, along the Arctic Ocean, with a population of roughly 1 million. Sakha comprises half of the area of its governing Far Eas ...
, the Korean Peninsula
Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...
[Karyakin, I. V. (2013). ''Review of the modern population status of the Steppe Eagle in the world and in Russia''. Raptors Conservation, (26).] and probably down to Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
in Asia.[ Migration sites include both mountainous ridges and the larger seas along their routes. Steppe eagles predominantly use two main migration routes: one radiates across the Middle East and Arabia, with many birds stopping to winter, but many too migrate around the ]Red Sea
The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...
to winter in Africa while the other main migration path frequently involves farther eastern breeding eagles moving along many ridges and prominent flyways before radiated across a broad path through the Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
, in order to reach the south Asia
South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...
n and other Asian wintering sites. Less known or less frequently migration paths before these well-known routes of passage may lead steppe eagles around the Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...
in the west and, much more frequently, around the Caspian Sea
The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...
farther east. Nations known to be visited by steppe eagles almost exclusively in migratory passage include Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, most but not all of Syria
Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...
, Turkmenistan
Turkmenistan ( or ; tk, Türkmenistan / Түркменистан, ) is a country located in Central Asia, bordered by Kazakhstan to the northwest, Uzbekistan to the north, east and northeast, Afghanistan to the southeast, Iran to the sout ...
and Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
and much of east China from Tuquan County
Tuquan County ( Mongolian: ''Tüčiuvan siyan'', Тучуань шянь; ) is a county of Inner Mongolia, People's Republic of China, facing Jilin province to the east. It is under the administration of Hinggan League, bordering Horqin Right Mi ...
to about Xiamen
Xiamen ( , ; ), also known as Amoy (, from Hokkien pronunciation ), is a sub-provincial city in southeastern Fujian, People's Republic of China, beside the Taiwan Strait. It is divided into six districts: Huli, Siming, Jimei, Tong'an, ...
. Points of migration bottleneck, where large numbers of steppe eagles are frequently recorded, are known in areas including Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
, especially around Eilat
Eilat ( , ; he, אֵילַת ; ar, إِيلَات, Īlāt) is Israel's southernmost city, with a population of , a busy port and popular resort at the northern tip of the Red Sea, on what is known in Israel as the Gulf of Eilat and in Jordan ...
, Suez
Suez ( ar, السويس '; ) is a seaport city (population of about 750,000 ) in north-eastern Egypt, located on the north coast of the Gulf of Suez (a branch of the Red Sea), near the southern terminus of the Suez Canal, having the same boun ...
(in Egypt), Bab-el-Mandeb
The Bab-el-Mandeb (Arabic: , , ) is a strait between Yemen on the Arabian Peninsula, and Djibouti and Eritrea in the Horn of Africa. It connects the Red Sea to the Gulf of Aden.
Name
The strait derives its name from the dangers attendin ...
(in Yemen), some parts of the nation of Georgia and, in the Himalayan region, especially within Nepal but also sometimes en masse in Pakistan and northern India
North India is a loosely defined region consisting of the northern part of India. The dominant geographical features of North India are the Indo-Gangetic Plain and the Himalayas, which demarcate the region from the Tibetan Plateau and Central ...
.[Welch, G., & Welch, H. (1991). ''The autumn migration of the Steppe Eagle Aquila nipalensis''. Sandgrouse, 13, 24–33.] Migration sites of minor significance are less known but include Alborz
The Alborz ( fa, البرز) range, also spelled as Alburz, Elburz or Elborz, is a mountain range in northern Iran that stretches from the border of Azerbaijan along the western and entire southern coast of the Caspian Sea and finally runs nort ...
.
Habitat
The steppe eagle tends to breeds in open dry country, within the characteristic habitat it is named after: the steppe
In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes.
Steppe biomes may include:
* the montane grasslands and shrublands biome
* the temperate grasslands, ...
both in both upland and lowland areas.[ In Kazakhstan, it is known to generally occur in drier parts of the steppe than some other raptors like harriers. This species generally avoids utilizing ]agricultural land
Agricultural land is typically land ''devoted to'' agriculture, the systematic and controlled use of other organism, forms of lifeparticularly the rearing of livestock and production of cropsto produce food for humans. It is generally synonymous ...
such as arables and most other human-fragmented areas, however, they can be somewhat tolerant of nesting near roads.[Sanchez-Zapata, J. A., Carrete, M., Gravilov, A., Sklyarenko, S., Ceballos, O., Donazar, J. A., & Hiraldo, F. (2003). ''Land use changes and raptor conservation in steppe habitats of Eastern Kazakhstan''. Biological Conservation, 111(1), 71–77.][Wassink, A., & Oreel, G. J. (2007). ''The birds of Kazakhstan''. A. Wassink.] Associated habitats are frequented when breeding such as flat plain
In geography, a plain is a flat expanse of land that generally does not change much in elevation, and is primarily treeless. Plains occur as lowlands along valleys or at the base of mountains, as coastal plains, and as plateaus or uplands ...
s, arid grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
, semi-desert
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-ar ...
and even desert edge.[ Most members of the species breed at lower levels but largely in eastern part of the range also will nest in poorly vegetated dry ]rocky
''Rocky'' is a 1976 American sports drama film directed by John G. Avildsen and written by and starring Sylvester Stallone. It is the first installment in the ''Rocky'' franchise and stars Talia Shire, Burt Young, Carl Weathers, and Burgess M ...
hill
A hill is a landform that extends above the surrounding terrain. It often has a distinct Summit (topography), summit.
Terminology
The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally con ...
sides such as granite
Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...
massif
In geology, a massif ( or ) is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole. The term also refers to a ...
s and upland valleys, though generally avoid truly mountainous areas.[ Wintering steppe eagles often occur much more frequently in human-modified areas in order to access easy foods. These include ]landfill
A landfill site, also known as a tip, dump, rubbish dump, garbage dump, or dumping ground, is a site for the disposal of waste materials. Landfill is the oldest and most common form of waste disposal, although the systematic burial of the waste ...
s and livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals ...
carcass
Carcass or Carcase (both pronounced ) may refer to:
*Dressed carcass, the body of a livestock animal ready for butchery, after removal of skin, visceral organs, head, feet etc.
*Carrion, the decaying dead body of an animal or human being
*The str ...
dumps, these being used frequently everywhere from Arabia to India.[ More natural habitats used most often by wintering steppe eagles tend to be various ]wetland
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
s or other waterway
A waterway is any navigable body of water. Broad distinctions are useful to avoid ambiguity, and disambiguation will be of varying importance depending on the nuance of the equivalent word in other languages. A first distinction is necessary b ...
s where they are available.[ In winter, mostly ]savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to ...
and grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s are the predominant habitat used in Africa, also sometimes dry woodland.[ Study in Botswana indicated that wintering steppe eagles there appeared to be indifferent to ]land use
Land use involves the management and modification of natural environment or wilderness into built environment such as settlements and semi-natural habitats such as arable fields, pastures, and managed woods. Land use by humans has a long h ...
changes by humans.[Herremans, M., & Herremans-Tonnoeyr, D. (2000). ''Land use and the conservation status of raptors in Botswana''. Biological Conservation, 94(1), 31–41.] In Zambia
Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most cent ...
and Malawi
Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeast ...
, it was found that the steppe eagle was only frequent in high-elevation plateau
In geology and physical geography, a plateau (; ; ), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. Often one or more sides ha ...
areas from metres above sea level
Height above mean sea level is a measure of the vertical distance (height, elevation or altitude) of a location in reference to a historic mean sea level taken as a vertical datum. In geodesy, it is formalized as ''orthometric heights''.
The comb ...
.[ Use of plateaus was also frequent in Zimbabwe, often where open savanna woods of '']Acacia
''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...
'' stand as well as the use of cultivated areas such as wheat stubble fields by eagles.[ Iraqi wintering steppe eagles often used dump sites as well as deserts and semi-arid areas, with more steppe, other grassland and mountain slopes used in northern Iraq in winter.][ In ]Armenia
Armenia (), , group=pron officially the Republic of Armenia,, is a landlocked country in the Armenian Highlands of Western Asia.The UNbr>classification of world regions places Armenia in Western Asia; the CIA World Factbook , , and ''Ox ...
steppe eagles are apparently frequent in old field
Field may refer to:
Expanses of open ground
* Field (agriculture), an area of land used for agricultural purposes
* Airfield, an aerodrome that lacks the infrastructure of an airport
* Battlefield
* Lawn, an area of mowed grass
* Meadow, a grass ...
s and orchard
An orchard is an intentional plantation of trees or shrubs that is maintained for food production. Orchards comprise fruit- or nut-producing trees which are generally grown for commercial production. Orchards are also sometimes a feature of larg ...
s.[Adamian, M. S., & Klem, D. (1999). ''Handbook of the Birds of Armenia''. American University of Armenia.] In south Asia
South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...
they usually use open country
"Open Country" is a designation used for some UK access land.
It was first defined under the National Parks and Access to the Countryside Act 1949 (and extended by the Countryside Act 1968), and was land over which an appropriate access agreeme ...
and often frequents large lake
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...
s and other wetland
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
s near arid areas but may accept, or even prefer, more heavily wooded areas (however the first records from peninsular Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
seem to be from open areas created by deforestation).[Ali, S., & Ripley, S. D. (1980). ''Handbook of the birds of India and Pakistan, together with those of Bangladesh, Nepal, Bhutan, and Sri Lanka''. Oxford University Press.] Although usually a breeder of lowlands, it has been known to live at elevations of up to and locally to in mountains, on passage can occur to over sometimes even to , as was recorded on Mount Everest
Mount Everest (; Tibetan: ''Chomolungma'' ; ) is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The China–Nepal border runs across its summit point. Its elevation (snow heig ...
.[ Compared to other ]Palearctic
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa.
The realm consists of several bioregions: the Euro-Sibe ...
migrating eagles, the steppe eagle seems to perhaps be slightly more tolerant of a wider range of climatic conditions, including rather humid
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present.
Humidity depen ...
conditions in India provided subsistence is available as well as up to of snow cover in Kazakhstan (living off of urban pests
PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...
).[Kataria, A. K., Kataria, N., & Kumawat, R. N. (2016). ''Effect of environmental elements on migration pattern of eagles at Jorbeer conservation reserve, Bikaner, Rajasthan, India''. Research Journal of life sciences, bioinformatics, pharmaceuticals and chemical sciences, 90–101.]
Behaviour
The steppe eagle is sometimes regarded as solitary but is frequently seen in the company of conspecifics throughout the year.[ Besides the obvious breeding pair, they often flock during migration and ]aggregate
Aggregate or aggregates may refer to:
Computing and mathematics
* collection of objects that are bound together by a root entity, otherwise known as an aggregate root. The aggregate root guarantees the consistency of changes being made within the ...
in occasionally ample numbers during non-breeding times, usually at fruitful feeding sites, sometimes briefly cooperating with one another especially to klepoparasitize other birds of prey.[ Steppe eagles fly with slow, deep and stiff-looking wing beats, holding wings fully extend on upstrokes, rendering a heavier flight pattern than ]spotted eagle
''Clanga'' is a genus which contains the spotted eagles. The genus name is from Ancient Greek ''klangos'', "eagle".
Species
Notes
References
{{Taxonbar, from=Q9160388
Clanga (genus),
Bird genera
Birds of ...
s. The flight of the steppe eagle is well-analyzed such as experiments with a captive male and observations of migrants in Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
.[Carruthers, A. C., Thomas, A. L., & Taylor, G. K. (2007). ''Automatic aeroelastic devices in the wings of a steppe eagle Aquila nipalensis''. Journal of Experimental Biology, 210(23), 4136–4149.][Gillies, J. A., Thomas, A. L., & Taylor, G. K. (2011). ''Soaring and maneuvering flight of a steppe eagle Aquila nipalensis''. Journal of Avian biology, 42(5), 377–386.] It appears that the underwing coverts operate as a high-lift device and probably provide stability through unsteady maneuvers, otherwise positive loading on the wings can be maintained. Whilst soaring, generally the wings are held flattish or slightly flexed but sometimes with the hands lowered.[ About 90% of flight by these eagles in Israel was gliding or soaring. They often fly with the head dropped with hands arched in a ]glide
Glide may refer to:
* Gliding flight, to fly without thrust
Computing
*Glide API, a 3D graphics interface
*Glide OS, a web desktop
*Glide (software), an instant video messenger
*Glide, a molecular docking software by Schrödinger (company), Schr ...
or often arms straight out and hands drooped.[ The drooping wing flight method, peculiar to the steppe eagle as well as to the ]greater spotted eagle
The greater spotted eagle (''Clanga clanga''), occasionally called the spotted eagle, is a large bird of prey. Like all typical eagles, it belongs to the family Accipitridae. Its feathered legs indicate it is a member of the subfamily Aquilinae ...
, is sometimes also called the "tuck", and is thought to be a gust response precipitated by a transient drop in aerodynamic loading. Steppes adapt their flight to wind and thermal conditions as was studied in Israel, increasing their gliding airspeed under strong thermal convections or opposing winds. This study determined that a combination of circling in thermals and inter-thermal gliding was interspersed with soaring in straight-line glide. Israeli migrants flew up to above the ground but 90% were under and half were below . The Israeli steppe eagles were able to maintain a mean climbing rate of per second, a mean cross-country air speed of per second and a mean of per second in glides; the flight was similar as in other common raptors here but the steppe eagle attained the highest mean cross-country speeds.[Spaar, R., & Bruderer, B. (1996). ''Soaring migration of Steppe Eagles Aquila nipalensis in southern Israel: flight behaviour under various wind and thermal conditions''. Journal of Avian Biology, 289–301.] Steppe eagles tend not to be very vocal especially when not breeding. Their main call is a raspy bark which is similar to that a tawny eagle, despite being mildly deeper. In aerial displays, a loud whistle has been recorded, quite unlike any vocalization of a tawny eagle. Other call recorded have included mainly low and croaking notes aside from a high shriek when startled.[
]
Migration
Steppe eagles appeared to have evolved the strategy of migrating from their breeding grounds, due in large part to the temporary seasonal availability of their main prey, ground squirrel
Ground squirrels are members of the squirrel family of rodents (Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known ...
s.[ They probably migrate in greater numbers than any other eagle in the world and can appear to be frequent enough at migration sites that they may mask less numerous migrating eagles that are mistakenly missed in their ranks. The migratory behaviour of this species is arguably amongst the best-studied aspect of its entire biology.][ Autumn migration often begins around October on fairly broad fronts, and may peak around late October.][ It usually ends in late November to December but steppe eagles frequently travel somewhat ]nomad
A nomad is a member of a community without fixed habitation who regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the popu ...
ically while not breeding and so individuals may not reach their winter terminus point until about January.[ Spring migration usually commences in February, peaking early from late February to March, with likely all gone from Africa by the end of the latter month, then continuing in a diminishing trickle into April and May.][Christensen, S., & Sorensen, U. G. (1989). ''A review of the migration and wintering of Aquila pomarina and Aquila nipalensis orientalis''. Raptors in the modern world. World Working Group on Birds of Prey, Berlin, Germany, 139–150.] In passage at Suez, the steppe eagle is one of the earlier migrating raptors on average alongside the long-legged buzzard
The long-legged buzzard (''Buteo rufinus'') is a bird of prey found widely in several parts of Eurasia and in North Africa. This species ranges from Southeastern Europe down to East Africa to the northern part of the Indian subcontinent. The long ...
(''Buteo rufinus''), averaging about a month sooner in passage than the common buzzard
The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. A member of the genus ''Buteo'', it is a member of the family Accipitridae. The species lives in most of Europe and extends its breeding range across ...
(''Buteo buteo'') (the most common migrant there) and slightly sooner than the lesser spotted eagle, as well as much sooner than some other raptors there. On average, the wintering period in Africa is relatively brief, at a mean of about up to about 4 months (down to about 2), while adult steppe eagles spend up to 7 months (max of around 5 months for a young eagle) on their breeding grounds.[Karyakin, I. V., Nikolenko, E. G., Shnayder, E. P., Zinevich, L. S., Pulikova, G. I., Bartoszuk, K., Horváth, M., Juhász, T., Aghababyan, K. & Andreyenkova, N. G. (2019). ''Results of the GPS/GSM-Tracking of Juvenile Steppe Eagles from Russia and Kazakhstan''. Raptors Conservation, (39).] In autumn records from Africa, younger eagles migrate the earliest and adults the latest.[Javed, S., Khan, S., Nazeer, J., Ahmed, S., Hammadi, A. A., & Hammadi, E. A. (2014). ''Satellite tracking of a young Steppe Eagle from the United Arab Emirates during two spring and autumn migrations''. Ostrich, 85(2), 131–138.] Radio-tagging studies confirmed, much as in the lesser spotted eagle
The lesser spotted eagle (''Clanga pomarina'') is a large Eastern European bird of prey. Like all typical eagles, it belongs to the family Accipitridae. The typical eagles are often united with the buteos, sea eagles, and other more heavy-set Acc ...
, that in spring juveniles migrated later, wandering about more so and came back to the summering grounds much later.[Meyburg, B. U., & Meyburg, C. (2010). ''Migration strategies of 16 Steppe Eagles Aquila nipalensis tracked by satellite''. In: ''The 6th International Conference on Asian Raptors'', Ulaanbaatar, Mongolia (pp. 23–27).] One young steppe eagle that was banded in passage in the United Arab Emirates
The United Arab Emirates (UAE; ar, اَلْإِمَارَات الْعَرَبِيَة الْمُتَحِدَة ), or simply the Emirates ( ar, الِْإمَارَات ), is a country in Western Asia (The Middle East). It is located at th ...
wintered initially in Yemen before returning for the summer to Kazakhstan, then migrating to eastern Africa the following winter, showing that they can change their migratory habits over time.[ Many studies corroborate that steppe eagles generally migrate lesser distances as they age.][Brooke, R. K., Grobler, J. H, Irwin, M. P. S., & Steyn, P. (1972). ''A study of the migratory eagles Aquila nipalensis and A. pomarina (Aves:Accipitridae) in Southern Africa, with comparative notes on other large raptors''. Occ. Papers of the Nat. Mus. of Rhodesia B5(2): 61–114.]
Peak movements around the Red Sea show as many as 76,000 steppe eagles moving over Bab-el-Mandeb in the fall of 1987, with up to 65,000 (in 1981) in Suez and up to 75,000 in Eilat
Eilat ( , ; he, אֵילַת ; ar, إِيلَات, Īlāt) is Israel's southernmost city, with a population of , a busy port and popular resort at the northern tip of the Red Sea, on what is known in Israel as the Gulf of Eilat and in Jordan ...
, Israel in the year 1985.[ Once migrating steppe eagles enter Africa in autumn, no mass migrations have been recorded anywhere for the species in the continent.][ Although not large, some semi-significant spring movements were detected in ]Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, despite none being recorded in the fall. In autumn, steppe eagles usually pass over Bab-el-Mandeb in the north of Red Sea while in spring they predominantly cross to the south of the Red Sea around Suez.[ The mean number of steppe eagles that annually pass over Eilat in spring are estimated at 28,032 with a mean peak day of 10 March, making them roughly the fourth most common migrating raptor in spring there (and they often pass in intermingled flocks with other soaring raptors, but not those with powered flight). In Eilat, steppe eagles constitute 6.4% of all raptors seen, nearly all of the ''Aquila'' eagles seen and, among those that could be aged, an estimated 60–70% of the steppes seen were thought to be adults. More unusually, the steppe eagle may be the only raptor to also use Israel as a common migratory flight path in autumn as well as spring, with even commoner migrating raptors such as ]common buzzard
The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. A member of the genus ''Buteo'', it is a member of the family Accipitridae. The species lives in most of Europe and extends its breeding range across ...
s and European honey buzzard
The European honey buzzard (''Pernis apivorus''), also known as the pern or common pern, is a bird of prey in the family Accipitridae.
Etymology
Despite its English name, this species is more closely related to kites of the genera '' Leptodon'' a ...
s (''Pernis apivorus'') being rare there in the fall. In Nepal over 2.5 weeks starting on 20 October, nearly 7852 steppe eagles were tallied, making up more than 80% of the recorded migrating raptors, with peak times of movement being between 10:00 AM and 4:00 PM, especially between noon and 2:00 PM.[De Roder, F. E. (1989). ''The migration of raptors south of Annapurna, Nepal, autumn 1985''. Forktail, 4, 9–17.] Over 3 years of study in Nepal, 21,447 steppe eagles were recorded (as many as 1102 within a day and a mean of about 15.2 an hour) at the counting sites.[Subedi, T. (2014). ''East to West Migration of Steppe Eagle Aquila nipalensis and other Raptors in Nepal: Abundance, Timing and Age Class Determination''. National Birds of Prey Trust, UK.] Strong evidence of east-to-west migratory movements, rather than south or northbound, has been made in the Kathmandu Valley
The Kathmandu Valley ( ne, काठमाडौं उपत्यका; also known as the Nepal Valley or Nepa Valley ( ne, नेपाः उपत्यका, Nepal Bhasa: 𑐣𑐾𑐥𑐵𑑅 𑐐𑐵𑑅, नेपाः गाः)), ...
. It was indicated based on the directional studies that especially juveniles from the eastern part of the breeding may be more frequently migrate westbound to reach wintering areas such as the Middle East and Africa.[ On the contrary, juveniles and subadults during the wintering season seem to considerably outnumber adults in the Indian subcontinent so many do head due south.][ Of 3381 ageable steppe eagles in passage in Nepal, 56% were juveniles or immature, 44% were adults; of 7852 eagles, 58% migrated in groups of 1–5, 30% in 5–20 groups and 12% in larger flocks.][ In ]Himachal Pradesh
Himachal Pradesh (; ; "Snow-laden Mountain Province") is a state in the northern part of India. Situated in the Western Himalayas, it is one of the thirteen mountain states and is characterized by an extreme landscape featuring several peaks ...
of India, about 11,000 steppe eagles were recorded in autumn migration in 2001 and about 40% less were counted the next spring. This study indicated different migratory paths being used in the seasons, presumably following the winds predominant direction around the terrain, with the westerly autumn migration mostly in the western Himalayas
The Western Himalayas refers to the western half of the Himalayas, in northern Pakistan and northwestern India. It is also known as the Punjab Himalayas. Four of the five tributaries of the Indus River in Punjab (Beas, Chenab, Jhelum, and Ravi) r ...
and the easterly spring migration more so in the east of Nepal. Staging areas are not well-delineated in India but appear to concentrate around feeding sites such as landfills.[Pande, S., Pawashe, A., Sant, N., Mahabal, A., & Dahanukar, N. (2010). ''Metropolitan garbage dumps: possible winter migratory raptor monitoring stations in peninsular India''. Journal of Threatened Taxa, 1214–1218.] A single female that was radio-tagged in Mongolia was recorded to travel southwest and stop in southeastern Tibet, which is also the southernmost part of the species breeding range. The data from this female indicated that not all steppe eagles move to warmer climates and, based on that she remained stationary until her return to Mongolia, that she was not nomadic as many eagles of the species are. During return spring migration, the steppe eagles in passage in Nepal will reportedly amass into groups of approximately 5 to 20 eagles at only about above the terrain before rising up to cross between the snow-covered peaks.[
]
16 radio-tagged eagles that returned in their first spring migration to their Kazakh summering grounds were recorded to winter as first-year juveniles either, in roughly equal measure, in the Arabian Peninsula or southern Africa, and covered straight-line distances, ranging from , although individually could meander up to for one eagle migrating from wintering grounds Botswana. Of the 16 returning Kazakhstan eagles, spring migration lasted an average of 40 days, ranging individually from 38 to 54 days and covered a mean of each day. The migration path generally led the eagles around almost every direction of the Red Sea, many also passing over Israel and some wrapping around the Caspian Sea.[ A different radio-tagging study of 19 juveniles (about 57% of which survived) from Russian or Kazakh sites found that autumn movements in the 1st year migration averaged and confirmed not only that they freely changed wintering sites anywhere from India to southern Africa but they never returned, surviving or not, to their natal site in the 1st year, instead return to wandering widely across the northern steppe. The 1st migration averaged 52 days and were much briefer for females than for males, with the discrepancies more pronounced for eagles originating from the ]Altai Mountains
The Altai Mountains (), also spelled Altay Mountains, are a mountain range in Central Asia, Central and East Asia, where Russia, China, Mongolia and Kazakhstan converge, and where the rivers Irtysh and Ob River, Ob have their headwaters. The m ...
. 15 birds tracked in this study were found to have migrated most frequently to winter in south Pakistan (right along the borderlands to India) or in eastern Turkmenistan
Turkmenistan ( or ; tk, Türkmenistan / Түркменистан, ) is a country located in Central Asia, bordered by Kazakhstan to the northwest, Uzbekistan to the north, east and northeast, Afghanistan to the southeast, Iran to the sout ...
. Spring migration began on a mean date of 25 March for the 15 young eagles and lasted about 26 days on average, covering a mean of , with females initiating migration on average 18 days later than males and migrating more briefly, more quickly and more often with fewer stops than males. 9 eagles which were tracked successfully in their first spring passage in this study wandering widely mostly in natural steppe hunting for squirrels and 8 of these tracked to their 2nd autumn migration took about 1.5 times shorter on their 2nd autumn passage and migrated about 17% less far on average.[
]
Dietary biology
The steppe eagle is an opportunistic predator like other ''Aquila'' eagles but has a number of dietary and foraging peculiarities. They prey mainly on small-sized mammals, with some bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
s (such as quelea
''Quelea'' is a genus of small passerine birds that belongs to the weaver family Ploceidae, confined to Africa. These are small-sized, sparrow- or finch-like gregarious birds, with bills adapted to eating seeds. Queleas may be nomadic over vas ...
s) and reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...
s and (mostly in winter) frequently insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s (such as termite
Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattode ...
s and locust
Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumstanc ...
s) and carrion
Carrion () is the decaying flesh of dead animals, including human flesh.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
.[ Despite their opportunistic nature, the steppe eagle is a somewhat specialized predator on particular mammals such as ]ground squirrel
Ground squirrels are members of the squirrel family of rodents (Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known ...
s while breeding and, during non-breeding times, feeds on various foods but is often peculiarly narrow in dietary selection, preferring massed food sources that require little effort for them to obtain.[ Various other small or medium-sized mammals can become the most significant prey locally on the breeding grounds, such as ]vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of low-c ...
s, pika
A pika ( or ; archaically spelled pica) is a small, mountain-dwelling mammal found in Asia and North America. With short limbs, very round body, an even coat of fur, and no external tail, they resemble their close relative, the rabbit, but wi ...
s and zokor
Zokors are Asiatic burrowing rodents resembling mole-rats. They include two genera: ''Myospalax'' and ''Eospalax''. Zokors are native to much of China, Kazakhstan, and Siberia, Siberian Russia.
Traditionally, zokors were thought to be closely ...
s and, generally more secondarily, marmot
Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, w ...
s, hare
Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The ge ...
s, gerbil
The Mongolian gerbil or Mongolian jird (''Meriones unguiculatus'') is a small rodent belonging to the subfamily Gerbillinae. Their body size is typically , with a tail, and body weight , with adult males larger than females. The animal is use ...
s, hedgehog
A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introducti ...
s and others.[ During the breeding season, one resource claimed that prey mostly weighs .][ Another account estimated that about 95% of prey weighed less than , although predominantly over .][ However, yet another resource claimed that staple prey for steppe eagles could weigh anywhere from up to .][Maming, R., & Zhao, X. M. (2013). ''Distribution Patterns and Ecology of the Steppe Eagle in China''. Raptors Conservation, (27).] Even the latter estimate may be conservative in size range, with prey species varying widely in size from very small insects from colonies to unexpectedly large mammals (and seldom birds) apparently killed near nests.[Pavlovich, I. M. (2015). ''About nesting of the Steppe Eagle Aquila nipalensis in Kalmykia''. Russian Ornithological Journal, 1221: 4321–4338.] On the other hand, a preference has indeed been detected for smaller burrowing mammals (i.e. probably under or so). Studies have determined where only larger species of burrowing mammals are predominant (even the larger species of ground squirrel), the steppe eagles appear to attain comparatively sparse nest densities, only occurring in high densities where the smaller burrowers are profuse.[ Ecological partitioning to limit interspecific competition may be a factor that dictates the steppe eagle's preference for relatively small prey.][ The breeding steppe eagle mainly hunts in a low soaring or gliding flight, at a maximum of , diving or making short, accelerated stoops onto their prey.][ Usually, they tend to capture their prey on the ground.][ Steppe eagles have been recorded in both Kazakhstan and Mongolia to tactfully avoid casting a shadow before descending onto prey and may drop stones to provide a distraction, a probable form of ]tool use
Tool use by animals is a phenomenon in which an animal uses any kind of tool in order to achieve a goal such as acquiring food and water, grooming, defence, communication, recreation or construction. Originally thought to be a skill possessed ...
. In the Kazakh observation, the steppe eagles quickly became used to agricultural activity adjacent to prey accesses while they hunted.[Ivanov, V. V. (2016). ''New in the Ecology of the Steppe Eagle Aquila nipalensis''. Russian Ornithological Journal, 1323: 3002–3003.][Tingay, R. E., Sureda, N., & Gilbert, M. (2008). ''Steppe Eagle (Aquila nipalensis) foraging behavior in Mongolia: a combined use of diversionary and covert ambush tactics''. Journal of Raptor Research, 42(2), 155–156.] They also may hunt in any season on the ground, moving with a shambling gait as necessary, and may give chase on foot to both vertebrate and insect prey. Steppe eagles can often ambush prey by standing in wait next to burrow
An Eastern chipmunk at the entrance of its burrow
A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of sh ...
s, suddenly pouncing quickly onto the quarry upon its emergence.[ Steppe eagles have been seen in China to buzz through ]locust
Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumstanc ...
swarms on the wing as well as to taking avian prey from over above the ground in a dive.[ Tandem hunting by pairs has been recorded during the breeding season while, in winter and migration, these may be the most social of all eagles, often sharing by up to the dozens abundant food sources. The non-breeding steppe eagle flocks may even seem to assist one another in procuring prey from which they themselves are not likely to be able to directly profit and may repeatedly assist each other until all flock members are satiated. If confirmed, this mutually beneficial foraging strategy between presumably unrelated eagles is truly unique.][ Much like the ]tawny eagle
The tawny eagle (''Aquila rapax'') is a large bird of prey. Like all eagles, it belongs to the family ''Accipitridae''. Its heavily feathered legs mark it as a member of the subfamily Aquilinae, also known as booted eagles.Helbig, A. J., Kocum, ...
, the steppe eagle will readily rob other raptors of their catches, approaching from any angle and pursuing closely until the victim is forced to land or drop its food.[
]
Summer diet
The single prey species most strongly associated with the steppe eagle is the little ground squirrel
The little ground squirrel or little souslik, (''Spermophilus pygmaeus'') is a species of rodent in the family Sciuridae. It is found from Eastern Europe to Central Asia.
Its subspecies include ''Spermophilus pygmaeus pygmaeus'', ''Spermophilus ...
(''Spermophilus pygmaeus'').[ In some areas, as much as 98% of the diet reportedly can be little ground squirrels.][ This is a smallish ground squirrel though it is actually not greatly smaller than many other Eurasian ground squirrels, at a mean adult weight of about .][Hayssen, V. (2008). ''Patterns of body and tail length and body mass in Sciuridae''. Journal of Mammalogy, 89(4), 852–873.] The little ground squirrel once reached densities of around 30–40 per hectare
The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is a ...
and provided a reliable food source for these eagles. However, this species has plummeted in population density, in Kalmykia
he official languages of the Republic of Kalmykia are the Kalmyk and Russian languages./ref>
, official_lang_list= Kalmyk
, official_lang_ref=Steppe Code (Constitution) of the Republic of Kalmykia, Article 17: he official languages of the ...
for instance going down from abundant in diverse habitats to perhaps locally extinct
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...
before gradually trickling back up in numbers (which continue to be a mere shadow of what they once were). The local steppe eagles of Kalmykia continue to show a strong preference for little ground squirrels.[ A continued primary reliance on little ground squirrels by steppe eagles was also found recent in studies from ]Saratov
Saratov (, ; rus, Сара́тов, a=Ru-Saratov.ogg, p=sɐˈratəf) is the largest city and administrative center of Saratov Oblast, Russia, and a major port on the Volga River upstream (north) of Volgograd. Saratov had a population of 901,36 ...
and Lake Baskunchak
Lake Baskunchak (russian: Баскунчак; kk, Басқұншақ, translit=Basqunshaq) is a salt lake of 115 km² in Astrakhan Oblast, Russia, located at , about 270 km north of the Caspian Sea, and 53 km east of the Volga. Sinc ...
as well.[Tabachishin, V. G., Zavyalov E. V., Khrustov, I. A. & Yakushev N. N. (2016). ''Steppe Eagle Aquila nipalensis in the Saratov Trans-Volga region''. Russian Ornithological Journal, 1310: 2580–2584.][Nikolaevich, A. P. (2011). ''Steppe Eagle Aquila nipalensis in the vicinity of Lake Baskunchak''. Russian Ornithological Journal, 692: 1937–1940.] Out of Russian, in the Karaganda Region
Karaganda Region ( kk, Qarağandy oblysy; russian: Карагандинская область, translit=Karagandinskaja oblast′), also spelled Qaraghandy Region, is a region of Kazakhstan. Its capital is Karaganda.
On 17 March 2022 it was an ...
of Kazakhstan, little ground squirrels again were an important identified food source, at 19.25% of 400 prey items.[Karyakin, I.V.,Nikolenko, E. G., Zinevich, L. S. & Pulikova, G. I. (2017). ''Steppe Eagle in the Karaganda Region, Kazakhstan''. Raptors Conservation, 35.] In the general area between the Aral Sea
The Aral Sea ( ; kk, Арал теңізі, Aral teñızı; uz, Орол денгизи, Orol dengizi; kaa, Арал теңизи, Aral teńizi; russian: Аральское море, Aral'skoye more) was an endorheic basin, endorheic lake lyi ...
and the Caspian Sea
The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...
, 112 prey items were led by little ground squirrels, at just over 33%. However, in this data, the little ground squirrels were closely followed in number (29.7%) by the yellow ground squirrel
The yellow ground squirrel (''Spermophilus fulvus'') is a large and sturdy ground squirrel species native to Afghanistan, China, Iran, Kazakhstan, Turkmenistan, Uzbekistan and Russia. It inhabits sandy steppes with Artemisia, glasswort and tamari ...
(''Spermophilus fulvus''), which, with seasonal weights ranging from , is the largest of Eurasian ground squirrels.[ The little ground squirrel is only found in a substantial portion of the western part of the range, so elsewhere steppe eagles tend to prey on different prey species while breeding, though generally continue to take small burrowing mammals, of course.][
]
Around Lake Balkhash
Lake Balkhash ( kk, Балқаш көлі, ''Balqaş kóli'', ; russian: озеро Балхаш, ozero Balkhash) is a lake in southeastern Kazakhstan, one of the largest lakes in Asia and the 15th largest in the world. It is located in the ea ...
in Kazakhstan, the main prey was reportedly the red-cheeked ground squirrel
The red-cheeked ground squirrel (''Spermophilus erythrogenys'') is a species of rodent in the family Sciuridae. It is commonly referred to as the red-cheeked ground souslik and there are several recognized subspecies. It is found in central Asia. ...
(''Spermophilus erythrogenys''), a slightly larger ground squirrel than the little species at a mean adult weight of . Other prey noted here included Pallas's pika
Pallas's pika (''Ochotona pallasi''), also known as the Mongolian pika, is a species of small mammals in the pika family, Ochotonidae. It is found mainly in the mountains of western Mongolia.
Description
Pallas's pika can range from anywhere be ...
(''Ochotona pallasi''), Libyan jird
The Libyan jird (''Meriones libycus'') is a species of rodent in the family Muridae. It is found in Mauritania, Morocco, Algeria, Tunisia, Libya, Egypt, Jordan, Syria, Saudi Arabia, Iran, Iraq, Afghanistan, Turkmenistan, Uzbekistan, Kazakhstan an ...
(''Meriones libycus'') and tolai hare
The tolai hare (''Lepus tolai'') is a species of hare native to Central Asia, Mongolia, and Northern and Central China. It inhabits semi-desert, steppes, rocky habitats, and forest meadows. It is relatively common, even in areas with heavy hu ...
(''Lepus tolai'').[Ivanovich, B. A. & Nikolaevich, B. N. (2013). ''On the Nesting of the Steppe Eagle Aquila nipalensis on the northeast coast of Lake Balkhash''. Russian Ornithological Journal, 862: 813–817.] In Xinjiang
Xinjiang, SASM/GNC: ''Xinjang''; zh, c=, p=Xīnjiāng; formerly romanized as Sinkiang (, ), officially the Xinjiang Uygur Autonomous Region (XUAR), is an autonomous region of the People's Republic of China (PRC), located in the northwest ...
, reportedly the main prey species is the long-tailed ground squirrel
The long-tailed ground squirrel or Eversmann's souslik (''Urocitellus undulatus'') is a species of rodent in the squirrel family Sciuridae. It is found in China, Kazakhstan, Mongolia, and Russia.
Description
The long-tailed ground squirrel has ...
(''Urocitellus undulatus'').[ In the Altai region, the leading prey may be the ]Siberian zokor
The Siberian zokor (''Myospalax myospalax'') is a species of rodent in the family Spalacidae. It is found in Kazakhstan and Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Nor ...
(''Myospalax myospalax''), which is the size of a large ground squirrel at an adult weight of about .[Karyakin, I.V., Smelyansky, I. E., Bakka, S. V., Grabovsky M. A., Rybenko A. V. & Egorov, E. V. (2005). ''Large feathered predators of the Altai Territory''. Raptor Research, 3: 28–54.] However, some report in the Altai region that the main prey is the long-tailed ground squirrel and the migration arrival times do seem to correspond closely with this species hibernation emergence period.[Mitrofanov, O.B. (2016). ''To the distribution of the steppe eagle Aquila nipalensis in the Altai Reserve''. Russian Ornithological Journal , 25 (1272).] Yet another primary prey resource reported for steppe eagles in the Altai is the much larger gray marmot (''Marmota baibacina''). All the primary prey in the previously little reported Altai population are as adults well over what is considered the typical prey size range for this eagle, such as long-tailed ground squirrels, zokors and marmots as well as ptarmigan
''Lagopus'' is a small genus of birds in the grouse subfamily commonly known as ptarmigans (). The genus contains three living species with numerous described subspecies, all living in tundra or cold upland areas.
Taxonomy and etymology
The ge ...
, and in turn, this may favor the large size of the steppe eagles from this region.[Barashkova, A.N., Smelyansky, I.E., & Tomilenko, A.A. (2009). ''Some information about the feathered predators of the Massiv Talduir kotr, southeastern Altai, Russia''. Feathered predators and their protection , (15).] On the contrary, other predominant prey in steppe eagle nests can be even smaller than ground squirrels. In Mongolia, the main prey by a large margin was reportedly the Brandt's vole
Brandt's vole, (''Lasiopodomys brandtii''), also known as the steppe vole, is a species of rodent in the family Cricetidae. It is native to shrublands and grasslands in Russia, Mongolia and northern China.
Characteristics
Brandt's vole is about ...
(''Lasiopodomys brandtii''), which weigh about .[Gombobaatar, S., Reuven, Y., Odkhuu, B., & Sumiya, D. (2012). ''Breeding ecology of the Steppe Eagle (Aquila nipalensis) in Mongolia''. Ornis Mongolica, (1), 13–19.] In the Transbaikal
Transbaikal, Trans-Baikal, Transbaikalia ( rus, Забайка́лье, r=Zabaykalye, p=zəbɐjˈkalʲjɪ), or Dauria (, ''Dauriya'') is a mountainous region to the east of or "beyond" (trans-) Lake Baikal in Far Eastern Russia.
The steppe and ...
region, the main prey may be the Daurian pika
The Daurian pika (''Ochotona dauurica'') is a small relative of rabbits and hares in the order Lagomorpha. It is well known for its “barking” alarm call, and for its peculiar habit of making hay to help survive the winter. There are 4 recogn ...
(''Ochotona dauurica''), which weighs about . This pika can account for around 39%, as was the case in 62 prey items, (and perhaps up to 62% locally) of the diet in the region.[Karyakin, I.V., Nikolenko, E.G., & Barashkova, A.N. (2012). ''Eagles of Dauria, Russia''. Feathered predators and their protection , (25).] Another study reported a very different primary food source for the Transbaikal, which was the young of the much larger Tarbagan marmot
The tarbagan marmot (''Marmota sibirica'') is a species of rodent in the family Sciuridae. It is found in China (Inner Mongolia and Heilongjiang), northern and western Mongolia, and Russia (southwest Siberia, Tuva, Transbaikalia). In the Mongoli ...
(''Marmota sibirica''), which were estimated in the study to be from 55 to 77% of the annual diet.[Peshkov, B. (2015). ''Some ecological features of the steppe eagle Aquila nipalensis in the eastern part of the range (Transbaikalia)''. Russian Ornithological Journal , 24 (1090).] Even more conflicting data found that some Transbaikal steppe eagles derived as much as 70% of their foods from long-tailed and Daurian ground squirrel
The Daurian ground squirrel (''Spermophilus dauricus'') is a species of rodent in the family Sciuridae. It is found in China, Mongolia, and Russia.
Distribution
The daurian ground squirrel has a wide range in north east China, extending into Mo ...
s (''Spermophilus dauricus'').[ It is possible that in both Altai and Transbaikal that the shifts to differing reported primary prey species are responses of the eagles to shifting prey availabilities as many burrowing mammals are subject to ]population cycle A population cycle in zoology is a phenomenon where populations rise and fall over a predictable period of time. There are some species where population numbers have reasonably predictable patterns of change although the full reasons for population ...
s as well as human-sourced depletions.[ While rodents and some lagomorphs are usually favored in the diet, in some areas steppe eagles can live at least in part off of quite different prey such as ]long-eared hedgehog
The long-eared hedgehog (''Hemiechinus auritus'') is a species of hedgehog native to Central Asian countries and some countries of the Middle East. The long-eared hedgehog lives in burrows that it either makes or finds and is distinguished by its ...
s (''Hemiechinus auritus''). Other notable prey taken regularly whilst breeding by steppe eagles includes steppe pika
The steppe pika (''Ochotona pusilla'') is a small mammal of the pika family, Ochotonidae. It is found in the steppes of southern Russia and northern Kazakhstan.
General description
Ochotonidae includes only one genus - ''Ochotona'', formed by ...
(''Ochotona pusilla'') (especially in the Volga region), alpine pika
The alpine pika (''Ochotona alpina'') is a species of small mammal in the pika family, Ochotonidae. The summer pelage of different subspecies varies drastically but, in general, it is dark or cinnamon brown, turning to grey with a yellowish tin ...
(''Ochotona alpina''), yellow steppe lemming
The yellow steppe lemming (''Eolagurus luteus'') is a species of rodent in the family Cricetidae.
It is found in China, Kazakhstan, and Mongolia. Its natural habitat is temperate desert
A desert is a barren area of landscape where little ...
(''Eolagurus luteus'') (especially in eastern Kazakhstan), or the slightly larger types of gerbil such as great gerbil
The great gerbil (''Rhombomys opimus'') is a large rodent found throughout much of Central Asia.
Description
The largest of the gerbils, great gerbils have a head and body length of . Their skulls are distinctive by having two grooves in each i ...
s (''Rhombomys opimus'') and Mongolian gerbil
The Mongolian gerbil or Mongolian jird (''Meriones unguiculatus'') is a small rodent belonging to the subfamily Gerbillinae. Their body size is typically , with a tail, and body weight , with adult males larger than females. The animal is us ...
s (''Meriones unguiculatus'').[ The study of the Karaganda region of Kazakhstan with 400 prey items found illustrated that the steppe eagle is capable of deriving a living from a wide range of prey, with the foods led by ]rosy starling
The rosy starling (''Pastor roseus'') is a passerine bird in the starling family, Sturnidae, also known as the rose-coloured starling or rose-coloured pastor. The species was recently placed in its own monotypic genus, ''Pastor'', and split fro ...
(''Pastor roseus'') (mostly fledglings), at 24%, unidentified ''Microtus
''Microtus'' is a genus of voles found in North America, Europe and northern Asia. The genus name refers to the small ears of these animals. About 62 species are placed in the genus. They are stout rodents with short ears, legs and tails. They ea ...
'' vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of low-c ...
s, at 19.75%, followed by little ground squirrels, unspecified pikas (8.25%), European hare
The European hare (''Lepus europaeus''), also known as the brown hare, is a species of hare native to Europe and parts of Asia. It is among the largest hare species and is adapted to temperate, open country. Hares are herbivorous and feed mainly ...
s (''Lepus europaeus'') (5%) and grey partridge
The grey partridge (''Perdix perdix''), also known as the gray-legged partridge, English partridge, Hungarian partridge, or hun, is a gamebird in the pheasant family Phasianidae of the order Galliformes, gallinaceous birds. The scientific name ...
s (''Perdix perdix'') (4.5%).[ An aptitude for avian prey was detected in Transbaikal particularly, including ]Daurian partridge
The Daurian partridge (''Perdix dauurica''), also known as steppe partridge, Asian grey partridge or bearded partridge, is a gamebird in the pheasant family Phasianidae of the order Galliformes (gallinaceous birds). Its name derives from the ...
(''Perdix dauurica'') and Japanese quail
The Japanese quail (''Coturnix japonica''), also known as the coturnix quail, is a species of Old World quail found in East Asia. First considered a subspecies of the common quail, it is now considered as a separate species. The Japanese quail ...
(''Coturnix japonica'') (the latter at up to 15.6% of the diet).[ In Altai, assorted ]corvid
Corvidae is a Cosmopolitan distribution, cosmopolitan family (biology), family of oscine passerine birds that contains the crows, ravens, rook (bird), rooks, jackdaws, jays, magpies, treepies, choughs, and nutcracker (bird), nutcrackers. In coll ...
s (at up to 24.2% of the diet), probably mostly rook
Rook (''Corvus frugilegus'') is a bird of the corvid family. Rook or rooks may also refer to:
Games
*Rook (chess), a piece in chess
*Rook (card game), a trick-taking card game
Military
* Sukhoi Su-25 or Rook, a close air support aircraft
* USS ...
s (''Corvus frugilegus'') and Eurasian magpie
The Eurasian magpie or common magpie (''Pica pica'') is a resident breeding bird throughout the northern part of the Eurasian continent. It is one of several birds in the crow family (corvids) designated magpies, and belongs to the Holarctic ra ...
(''Pica pica''), were important to diet as were willow ptarmigan
The willow ptarmigan () (''Lagopus lagopus'') is a bird in the grouse subfamily Tetraoninae of the pheasant family Phasianidae. It is also known as the willow grouse and in Ireland and Britain, where the subspecies '' L. l. scotica'' was previo ...
(''Lagopus lagopus'').[ Within the Saratov area, medium-sized birds were frequently reported in the diet, such as grey partridges, ]little bustard
The little bustard (''Tetrax tetrax'') is a bird in the bustard family, the only member of the genus ''Tetrax''. The genus name is from Ancient Greek and refers to a gamebird mentioned by Aristophanes and others. Distribution
It breeds in Southe ...
s (''Tetrax tetrax''), northern lapwing
The northern lapwing (''Vanellus vanellus''), also known as the peewit or pewit, tuit or tew-it, green plover, or (in Ireland and Britain) pyewipe or just lapwing, is a bird in the lapwing subfamily. It is common through temperate Eurosiberia. ...
s (''Vanellus vanellus'') and rooks.[ A diversity of small passerines has been found in the diet, especially fledgling-age ]lark
Larks are passerine birds of the family Alaudidae. Larks have a cosmopolitan distribution with the largest number of species occurring in Africa. Only a single species, the horned lark, occurs in North America, and only Horsfield's bush lark occu ...
s of various species, most frequently perhaps in Kazakhstan and Mongolia.[ A few reptiles found in the diet around nest have included at least ]sand lizard
The sand lizard (''Lacerta agilis'') is a lacertid lizard distributed across most of Europe from France and across the continent to Lake Baikal in Russia. It does not occur in European Turkey. Its distribution is often patchy. In the sand lizard ...
(''Lacerta agilis''), Caspian whipsnake
The Caspian whipsnake (''Dolichophis caspius'', sometimes also ''Coluber caspius'') also known as the large whipsnake (among various other species in genus ''Dolichophis''/'' Coluber''), is a common species of whipsnake found in the Balkans ...
(''Dolichophis caspius'') and steppe viper
:''Common names: meadow viper, Ursini's viper, Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. . meadow adder,Brown, John Haynes (1973). ''To ...
(''Vipera ursinii'').[
]
On occasion, during summer, a steppe eagle may be able to take exceptionally large prey. The most regular large prey to appear in their diets are usually Tolai hare, at about , and assorted marmot
Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, w ...
s. The upper size of marmots that the steppe eagle may attack is not well-established although all of the species regularly hunted by these eagles have extremely large average adult weights, i.e. around , but the typical size taken by this eagle is more likely around (i.e. for small emergent juvenile marmots).[ The steppe eagle takes a diversity of mammalian ]carnivores
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...
including mountain weasel
The mountain weasel (''Mustela altaica''), also known as the pale weasel, Altai weasel or ''solongoi'', primarily lives in high-altitude environments, as well as rocky tundra and grassy woodlands. This weasel rests in rock crevices, tree trunks, ...
(''Mustela atlaica''), marbled polecat
The marbled polecat (''Vormela peregusna'') is a small mammal belonging to the monotypic genus ''Vormela'' within the mustelid subfamily Ictonychinae. ''Vormela'' is from the German word , which means "little worm". The specific name ''peregusn ...
(''Vormela peregusna''), steppe polecat (''Mustela eversmanii''), kits of Eurasian badger
The European badger (''Meles meles''), also known as the Eurasian badger, is a badger species in the family Mustelidae native to almost all of Europe. It is classified as least concern on the IUCN Red List as it has a wide range and a large stabl ...
(''Meles meles'') and possibly live adults (i.e. "fresh remains") of corsac fox
The corsac fox (''Vulpes corsac''), also known simply as a corsac, is a medium-sized fox found in steppes, semi-deserts and deserts in Central Asia, ranging into Mongolia and northern China. Since 2004, it has been classified as ''least concern ...
(''Vulpes corsac'') and red fox
The red fox (''Vulpes vulpes'') is the largest of the true foxes and one of the most widely distributed members of the Order (biology), order Carnivora, being present across the entire Northern Hemisphere including most of North America, Europe ...
(''Vulpes vulpes'').[ A surprisingly range of young ]ungulate
Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...
s have also been found in small numbers and it is likely that some are taken both as carrion and as kills, including goitered gazelle (''Gazella subgutturosa''), Mongolian gazelle
The Mongolian gazelle (''Procapra gutturosa''), or dzeren (russian: Дзерэн), is a medium-sized antelope native to the semiarid Central Asian steppes of Mongolia, as well as some parts of Siberia and China. The name ''dzeren'' is Russian mis ...
(''Procapra gutturosa''), saiga antelope
The saiga antelope (, ''Saiga tatarica''), or saiga, is a critically endangered antelope which during antiquity inhabited a vast area of the Eurasian steppe spanning the foothills of the Carpathian Mountains in the northwest and Caucasus in ...
(''Saiga tatarica'') and domestic goat
The goat or domestic goat (''Capra hircus'') is a domesticated species of goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the a ...
(''Capra aegagrus hircus''). In newborns of these species, weights can vary from around (in goats) to about (in saiga antelope).[ The taking of large birds is less well-documented than predation on large mammals and in some cases both in summer and during non-breeding times certainly pertain to nestling predations, such as on ]stork
Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family called Ciconiidae, and make up the order Ciconiiformes . Ciconiiformes previously included a number of other families, such as herons an ...
s and cranes, or to pilfering easy large fowl
Fowl are birds belonging to one of two biological orders, namely the gamefowl or landfowl (Galliformes) and the waterfowl (Anseriformes). Anatomical and molecular similarities suggest these two groups are close evolutionary relatives; together ...
like chicken
The chicken (''Gallus gallus domesticus'') is a domesticated junglefowl species, with attributes of wild species such as the grey and the Ceylon junglefowl that are originally from Southeastern Asia. Rooster or cock is a term for an adult m ...
s (''Gallus gallus domesticus'') or domestic turkey
The domestic turkey (Meleagris gallopavo domesticus) is a large fowl, one of the two species in the genus '' Meleagris'' and the same species as the wild turkey. Although turkey domestication was thought to have occurred in central Mesoamerica a ...
s (''Meleagris gallopavo'').[Horváth, M., Béres, I., Özcan, C., Juhász, T., Kovács, A., Tatar, B., Karyakin, I., Schmidt, M. &Tavares J. (2019). ''Breeding Population Surveys of Eastern Imperial Eagles and Steppe Eagles in Central Anatolia''. Report presented on the II International Scientific and Practical Conference ''Eagles of Palearctic: Study and Conservation''.]
Non-breeding diet
The steppe eagle, despite being one of the most numerous and widely distributed of all eagles, is exceptionally poorly studied in its non-breeding dietary habits. This is due in large part to the nomadic behaviour displayed by most (but not all) steppe eagles during these times. Steppe eagles are fairly different from related species, being rather gregarious and non-predatory while away from their breeding grounds.[ Exceptionally, some steppe eagles have been known to overwinter in Altai Town, Kazakhstan, living reportedly off of ]brown rat
The brown rat (''Rattus norvegicus''), also known as the common rat, street rat, sewer rat, wharf rat, Hanover rat, Norway rat, Norwegian rat and Parisian rat, is a widespread species of common rat. One of the largest muroids, it is a brown o ...
s (''Rattus norvegicus'') and rock dove
The rock dove, rock pigeon, or common pigeon ( also ; ''Columba livia'') is a member of the bird family Columbidae (doves and pigeons). In common usage, it is often simply referred to as the "pigeon".
The domestic pigeon (''Columba livia domes ...
s (''Columba livia'').[ They are often seen congregating at feeding sites with easily obtained foods that are available in large quantities. In ]southern Africa
Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of ...
, these eagles are often associated with rain fronts and the humidity
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present.
Humidity depe ...
that accompanies them.[ They do this largely to exploit a certain food source, ]termite
Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattode ...
alate
Alate (Latin ''ālātus'', from ''āla'' (“wing”)) is an adjective and noun used in entomology and botany to refer to something that has wings or winglike structures.
In entomology
In entomology, "alate" usually refers to the winged form o ...
s. Termites are known to emerge more extensively in these conditions and so the steppe eagle, not unlike other long-distance migrant raptors, can become locally rather insectivorous
A robber fly eating a hoverfly
An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects.
The first vertebrate insectivores were ...
to the exception of virtually any other foods.[Jensen, H. H. (1972). ''The Steppe Eagle Aquila nipalensis and other termite-eating raptors in South West Africa''. Madoqua, 1972(Series 1 Issue 5), 73–76.] Most often, these eagles will fly down when it is noticed that termites are emerging or wait on foot and then grab them.[ According to one account these large eagles feed on termites "lumbering after their minuscule quarry in ludicrous fashion".][ They have also sometimes been seen to take termites in the air and feed on them in flight, not any easy task for such a large eagle.][ Roosts near termite colonies can contain several steppe eagles which may remain over days but generally depart whether well-fed or not if the rains disperse. In ]Namibia
Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...
, the roosts used were the tops of quite small trees of only height.[ Although tiny with an average estimated weight of only , the ]harvester termite
The harvester termites (from Greek ὁδός (hodós), travelling; Latin '' termes'', woodworm) are an ancient, Old World family of termites, the Hodotermitidae. They are distinguished by the serrated inner edge of their mandibles, and their func ...
(''Hodotermes mossambicus'') (the main termite prey) have been deemed highly nutritious with a relatively high caloric value. It has been estimated that a steppe eagle would have to eat approximately 1600–2200 termites a day, which can be attainable in about 3 hours of feeding.[ The stomachs of 2 dissected steppe eagles contained 630 and 930 termite heads, respectively.][ In Zimbabwe, steppe eagles have also been seen in feeding masses in stubble fields picking out insects.][ However, it would reductive to consider the steppe eagle largely insectivorous in winter, since disproportionately the eagles seen feeding on termites in southern Africa were juveniles and immatures and many of the species winter outside of southern Africa; often wintering steppe eagles from other areas do not seem to live predominantly on insects.][ In ]east Africa
East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa:
Due to the historical ...
, the diet of steppe eagles is poorly documented but is reported to consist largely of silvery mole-rats (''Heliophobius argenteocinereus'') and blesmol
The blesmols, also known as mole-rats, or African mole-rats, are burrowing rodents of the family Bathyergidae. They represent a distinct evolution of a subterranean life among rodents much like the pocket gophers of North America, the tuco-tuc ...
s of the genus ''Cryptomys
''Cryptomys'' is the genus of mole-rats, endemic to Africa. Most of the species formerly placed in this genus were moved to the genus ''Fukomys
''Fukomys'' is a genus described in 2006 of common blesmol, mole-rats, containing several species ...
''.[Meyburg, B.U., P. F. D. Boesman, J. S. Marks, and C.J. Sharpe (2020). ''Steppe Eagle (Aquila nipalensis)'', version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA.] Routine predation, probably on young or weak individuals, by steppe eagles has been recorded amongst flamingo
Flamingos or flamingoes are a type of Wader, wading bird in the Family (biology), family Phoenicopteridae, which is the only extant family in the order Phoenicopteriformes. There are four flamingo species distributed throughout the Americas ...
colonies in east Africa. In several parts of Africa, steppe eagles may routinely visit and feed off of the colonies of the super-abundant bird, the red-billed quelea
The red-billed quelea (; ''Quelea quelea''), also known as the red-billed weaver or red-billed dioch, is a small—approximately long and weighing —migratory, sparrow-like bird of the weaver family, Ploceidae, native to Sub-Saharan Africa.
...
(''Quelea quelea''), with a noted focus on picking off the seemingly innumerous nestlings and fledglings of this small passerine. The steppe eagles will reportedly do so by ungracefully scrambling amongst the branches of the nesting colonies.[
In the Indian subcontinent, the steppe eagle appears to fulfill the role of a weakly predatory opportunist.][ Individual Indian wintering steppe eagles are reported to feed at times of vulnerability of prey, including injured birds, eggs and young ]water bird
A water bird, alternatively waterbird or aquatic bird, is a bird that lives on or around water. In some definitions, the term ''water bird'' is especially applied to birds in freshwater ecosystems, although others make no distinction from seabi ...
s from heronries, while groups of the eagles often occur around carrion
Carrion () is the decaying flesh of dead animals, including human flesh.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
, masses of stranded fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
, poultry farms, garbage dumps
A landfill site, also known as a tip, dump, rubbish dump, garbage dump, or dumping ground, is a site for the disposal of waste materials. Landfill is the oldest and most common form of waste disposal, although the systematic burial of the waste ...
and livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals ...
carcass dumps.[Pande, S. A., Mahabal, A. S., Deshpande, P., & Sharma, R. M. (2013). ''Distribution of the Steppe Eagle in the Indian Subcontinent: An Overview from 1882 to 2013''. Feathered predators and their protection, (27).] In Chari-Dhand wetlands, as many as 1000 steppe eagles have been seen to gather, presumably living largely off of vulnerable water birds.[ At the city dumps of ]Pune
Pune (; ; also known as Poona, (List of renamed Indian cities and states#Maharashtra, the official name from 1818 until 1978) is one of the most important industrial and educational hubs of India, with an estimated population of 7.4 million ...
as many as 200 steppe eagles have been known to gather and feed.[ A carcass dump in Jorbeer near ]Bikaner
Bikaner () is a city in the northwest of the state of Rajasthan, India. It is located northwest of the state capital, Jaipur. Bikaner city is the administrative headquarters of Bikaner District and Bikaner division.
Formerly the capital of ...
was recorded to host an average of 43 steppe eagles per day during winter, with a peak number generally occurring in January and February (common dates from November to March and more rarely from September to May), with as many as 136 steppe eagles plus at least 9 other large raptors (mostly vultures), many of which are considered threatened species. It was found the Jorbeer carcass dumps enticed the steppe eagles to venture away from the normal wetland or wetland-adjacent areas used by steppe eagles in the area to the desert-like region, but feral dogs
A free-ranging dog is a dog that is not confined to a yard or house. Free-ranging dogs include street dogs, village dogs, stray dogs, feral dogs, etc., and may be owned or unowned. The global dog population is estimated to be 900 million, of w ...
could, in some years, appear to chase off and cause the eagles to avoid this dump.[Sharma, P., & Sundar, K. S. (2009). ''Counts of Steppe Eagles Aquila nipalensis at a carcass dump in Jorbeer, Rajasthan, India''.] A concentration of around 50 steppe eagle was seen to feed on swarms of locust
Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumstanc ...
s in Nepal. Perhaps to avoid competition (i.e. from vultures
A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including Condors). Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to North and So ...
, jackals
Jackals are medium-sized canids native to Africa and Eurasia. While the word "jackal" has historically been used for many canines of the subtribe canina, in modern use it most commonly refers to three species: the closely related black-backed ...
and so on) and to monopolize a food item, steppe eagles in India appear to come largely to smaller carcasses such as those of jungle cat
The jungle cat (''Felis chaus''), also called reed cat, swamp cat and jungle lynx, is a medium-sized cat native to the Middle East, the Caucasus, South and Southeast Asia and southern China. It inhabits foremost wetlands like swamps, littora ...
s (''Felis chaus'') and pythons
The Pythonidae, commonly known as pythons, are a family of nonvenomous snakes found in Africa, Asia, and Australia. Among its members are some of the largest snakes in the world. Ten genera and 42 species are currently recognized.
Distribution ...
.[ In the ]Banni Grasslands Reserve
Banni Grasslands Reserve or Banni grasslands form a belt of arid grassland ecosystem on the outer southern edge of the desert of the marshy salt flats of Rann of Kutch in Kutch District, Gujarat State, India. They are known for rich wildlife a ...
, steppe eagles are reported to largely hunt for food unlike in many other Indian reports, mainly on lesser bandicoot rat
The lesser bandicoot rat, Sindhi rice rat, bengal rat or Indian mole-rat (''Bandicota bengalensis'') is a giant rat of South Asia, Southern Asia, not related to the true bandicoots which are marsupials. They can be up to 40 cm long (includin ...
s (''Bandicota bengalensis''), although also sometimes stole prey from other raptors.[ Similarly, active predation was unusually reported in Saurashtra and on larger prey including ]mongoose
A mongoose is a small terrestrial carnivorous mammal belonging to the family Herpestidae. This family is currently split into two subfamilies, the Herpestinae and the Mungotinae. The Herpestinae comprises 23 living species that are native to so ...
and Indian hare
The Indian hare (''Lepus nigricollis''), also known as the black-naped hare, is a common species of hare native to the Indian subcontinent, and Java.
Introductions
It has been introduced to Madagascar, Comoro Islands, Andaman Islands, Irian Jay ...
(''Lepus nigricollis'') as well as an unsuccessful attack on a mountain gazelle
The mountain gazelle (''Gazella gazella''), also called the Palestine mountain gazelle, is a species of gazelle widely but unevenly distributed.
Description
Mountain gazelle are one of the few mammals in which both sexes have horns. Males ha ...
(''Gazella gazella'') fawn.[Dharmakuarsinhji, K.S. (1955). ''Birds of Saurashtra''. Dil Bahar.]
In the region of Bharatpur, Rajasthan
Bharatpur is a city in the Indian state of Rajasthan, south of India's capital, New Delhi, from Rajasthan's capital Jaipur, west of Agra of Uttar Pradesh and from Mathura of Uttar Pradesh. It is the administrative headquarters of Bharatp ...
, largely around Keoladeo National Park
Keoladeo National Park or Keoladeo Ghana National Park (formerly known as the Bharatpur Bird Sanctuary) is a famous Bird, avifauna sanctuary in Bharatpur, India, Bharatpur, Rajasthan, India, that hosts thousands of birds, especially during the w ...
, the foraging activities of steppe eagles have been observed extensively. The steppe eagles seldom actively hunted, instead alternating between capturing nestlings from the heronries
A heronry, sometimes called a heron rookery, is a breeding ground for herons.
Notable heronries
Although their breeding territories are often on more protected small islands in lakes or retention ponds, herons breed in heronries (or also called ...
, especially nearly fledgling-age young of late nesting painted stork
The painted stork (''Mycteria leucocephala'') is a large wading bird, wader in the stork family. It is found in the wetlands of the plains of tropical Asia south of the Himalayas in the Indian Subcontinent and extending into Southeast Asia. Thei ...
s (''Mycteria leucocephala''), and engaging in kleptoparasitism
Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when foo ...
towards other birds of prey, often doing so in groups of about three to nine eagles. More infrequently, steppe eagles in Bharatpur have been seen hunting flocking birds, fish (usually stranded), lizard
Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...
s and snake
Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...
s. The steppes have been observed feeding on freshly killed young water birds at Bharatpur at daybreak and during early mornings and so may hunt while taking advantage of bright moonlight. Piracy against other raptors often resulted in food wastage, since the steppe eagles often forced the other raptors to drop their catch but the steppes were unable to intercept them and the kills were frequently lost into the water. In Bharatpur, the steppe eagles tended to perch relatively low compared to other eagles, at about in the trees, and to perch often for longer periods than other raptors, apparently while watching closely the activity of the other birds of prey. Of a total of 49 observed hours of activity for steppe eagles in Bharatpur, 45% of it was spent foraging, with a maximum foraging time of 69% during January, then reduced in March to only 17%. The daily food intake of individual steppe eagles was extremely low relative to their size, at only . Instead of piracy, the steppe eagles often engaged each other in what can be considered a play display, almost exclusively between juvenile steppe eagles. In it, two birds circled or more, the higher bird circling closer and dropping toward the lower bird with extended feet, forcing it to roll over and present talons, they either immediately disengage with or without locking talons or descend looked for a few metres before separating; often steppes will fly purposely at a conspecific that is circling and fly up to a higher position so it can drop onto the other; in another incident, a steppe grabbed a plastic bag and let it go buffeting by the wind, then repeatedly caught it and let it go again, ultimately being joined by 5–6 other steppes in the "game'.[Prakash, V. (1988). ''The general ecology of raptors in Keoladeo National Park, Bharatpur'' (Doctoral dissertation, PhD thesis. Bombay University, Mumbai, India).][Naoroji, R. (1990). ''Predation by Aquila eagles on nestling storks and herons in Keoladeo National Park, Bharatpur''. Journal of the Bombay Natural History Society, 80087(1), 37–46.]
Less study has been conducted on feeding habits of the wintering and migrating steppe eagles in the Asia Minor
Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The re ...
, Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
and Arabian Peninsula
The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...
. What is known suggests that they, even more strongly than wintering steppe eagles in Indian subcontinent, today frequent various waste food sources inadvertently provided to them by humans. In Muscat
Muscat ( ar, مَسْقَط, ) is the capital and most populated city in Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is s ...
, Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of t ...
, migrants largely from Kazakhstan were recorded to live off a mixture of refuse from the region's main landfill and large-scale carcass dump sites. As in the carcass dump areas of the Indian subcontinent, these carcass dumps often host a wide array of large birds of prey, both migrating species and non-migratory ones. In keeping with its size, steppe eagles dominated slightly smaller eagles and vultures and were in turn dominated by slightly larger eagles
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
and much larger vultures
A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including Condors). Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to North and So ...
.[Prohl, T., & Baumgart, W. (2012). ''An Überwinterungsplätzen des Step-penadlers (Aquila nipalensis) und an-derer großer aasverwertender Greif-vögel im Oman''. Greifvögel und Falknerei, 2012, 47–72.] High use of slaughterhouse
A slaughterhouse, also called abattoir (), is a facility where animals are slaughtered to provide food. Slaughterhouses supply meat, which then becomes the responsibility of a packaging facility.
Slaughterhouses that produce meat that is no ...
s and cattle
Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult mal ...
dump sites was recorded in winter in Iran. Interestingly, the Iranian slaughterhouses and dump sites hosted no first-year juveniles and few adults, but many steppe eagles either aged to 2 to 3 years of age (62.5%) or 4 to 5 years of age (33.3%).[Shafaipour, A., Nia, F. & Khanjani. (2018). ''Aquila nipalensis and Aquila heliaca surveys of wintering grounds around the slaughterhouse and Yasuj garbage site from the fall of 2015 to the winter of 2016''. Animal Environment, 10 (3), 101–106.] Foraging in both dump sites and available wetlands has been recorded in Iraq as well.[ Incidental feeding observations from ]Armenia
Armenia (), , group=pron officially the Republic of Armenia,, is a landlocked country in the Armenian Highlands of Western Asia.The UNbr>classification of world regions places Armenia in Western Asia; the CIA World Factbook , , and ''Ox ...
suggests that steppe eagles in passage and in winter there are able to capture large quantities of vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of low-c ...
s or pirate them or similar small prey from smaller species of birds of prey.[
]
Interspecific predatory relationships
The steppe eagle shares its distribution with several other birds of prey that can compete for resources. Most similar in feeding niche are largely other eagle
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
s, many of which are also similarly migratory. One eagle of similar central distribution is the eastern imperial eagle
The eastern imperial eagle (''Aquila heliaca'') is a large bird of prey that breeds in southeastern Europe and extensively through West and Central Asia. Most populations are migratory and winter in northeastern Africa, the Middle East and South ...
s.[ The imperial eagle has a similar morphology and can broadly overlap in food selection.][ It also takes many ground squirrels but is generally less specialized on them during breeding, and often takes similar or larger numbers of prey such as ]hare
Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The ge ...
s, hedgehog
A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introducti ...
s, hamster
Hamsters are rodents (order Rodentia) belonging to the subfamily Cricetinae, which contains 19 species classified in seven genera.Fox, Sue. 2006. ''Hamsters''. T.F.H. Publications Inc. They have become established as popular small pets. The b ...
s and assorted birds both large and medium. In general, the dietary biology is better understood, prey is taken of more diverse sizes and the prey spectrum is far more diverse (perhaps nearly three times as many recorded prey species) in the imperial species.[Horváth, M., Solti, B., Fatér, I., Juhász, T., Haraszthy, L., Szitta, T., Bállok, Z. & Pásztory-Kovács, S. (2018). ''Temporal changes in the diet composition of the Eastern Imperial Eagle (Aquila heliaca) in Hungary''. Ornis Hungarica, 26(1), 1–26.] The average weight taken of prey like young marmots is similar in both eagles, averaging in the eastern imperial while the steppe also takes marmots of around this size.[Katzner, T. E., Bragin, E. A., Knick, S. T., & Smith, A. T. (2006). ''Spatial structure in the diet of imperial eagles Aquila heliaca in Kazakhstan''. Journal of Avian Biology, 37(6), 594–600.] Although not common, the imperial eagle can sometimes take prey weighing over , probably rather more frequently than the steppe eagle.[ It is possible that the steppe eagle gained the preference for relatively more numerous and social but quite small mammals as prey to avoid heavier competition over slightly larger but often more dispersed terrestrial mammals (i.e. hares, hedgehogs, etc.), especially those taken by imperial eagles.][ Also, the imperial eagle is rather more predatory in food obtainment while wintering, not infrequently eschewing the more vulnerable nestling water birds in the Indian subcontinent to take many adult birds such as ]waterfowl
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...
and coots
Coots are medium-sized water birds that are members of the rail family, Rallidae. They constitute the genus ''Fulica'', the name being the Latin term for "coot". Coots have predominantly black plumage, and—unlike many rails—they are usually ...
.[ The eastern imperial eagle differs most significantly from steppe eagles in nesting habits, favoring tall trees, sometimes in fairly well-wooded areas, which quite contrary to the steppe eagles ground nesting preferences. The migratory course used by imperial eagles is largely the same as the steppe eagle but the imperial is the far less numerous migrant (also more frequently overwintering near their breeding ground) and radiates less far in winter (especially in Africa).][ Despite the steppe eagle averaging scarcely smaller, data from both breeding and wintering areas indicates that the imperial eagle tends to be behaviorally dominant over steppe eagles. This has manifested in full or partial displacement of steppe eagles locally using pylons as nesting sites by imperial eagles. Furthermore, at shared feeding sites, the steppe eagle tends to back down to the imperial eagle, often allowing it to feed first despite occasional displacement of imperials with full crops.][ On occasion, in India, steppe eagles succeed in pirating prey from imperial eagles, normally in cooperating parties of steppe eagles.][ In at least one case in India, the steppe eagle was the aggressor in an interaction with an eastern imperial eagle, causing the two eagles to lock talons and cartwheel down with uncertain results.][ While the eagles are expected to correspond their sizes in hierarchy when nests are located in the same general area, with the steppe considered as generally subordinate to the imperial which is itself subordinate to the golden eagle, interactions in the Altai region suggest a more complex interspecific relationship. There one study reported several aggressive interactions with both imperial and golden eagles and the steppes were surprisingly the aggressors in each. In one instance, a golden eagle was fiercely attacked by a steppe eagle who appeared to dominate the interaction, grabbing the more formidable-armed golden in air and driving it forcefully to the ground (although the golden eagle was not killed).][Markovich, V. V. & Fedorovich, B. R. (2019). ''State of study of the Steppe Eagle Aquila nipalensis in Altai''. Russian Ornithological Journal, 1847: 5247–5261.]
Much has been written about what separates the steppe from the tawny eagle but little to no interactions between the species have been noted in the wild.[ Beyond being strongly ]allopatric
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...
, wintering steppe eagles usually use slightly different habitats, favoring available wetlands quite apart from the arid wooded savanna and semi-desert areas preferred by tawny eagles.[ The tawny eagle, despite being smaller and proportionately similar in talon size (with a considerably less massive gape), is a rather more powerful and bold predator than the steppe eagle, alternating between capturing relatively large prey, pirating prey from other raptors and scavenging on carrion.][ The prey sizes taken by tawny eagles are perhaps the most evenly distributed across all weight classes besides the eastern imperial and golden eagles amongst ''Aquila'' and ''Clanga'' species, with a focus on prey weighing from , i.e. well over the typical prey sizes for steppe eagles in any area.]