The red-tailed hawk (''Buteo jamaicensis'') is a
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 ...
that breeds throughout most of North America, from the interior of
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
and northern Canada to as far south as
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...
and the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greater A ...
. It is one of the most common members within the genus of ''
Buteo
''Buteo'' is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in the New World (Etymology: ''Buteo'' is the Latin name o ...
'' in North America or worldwide.
The red-tailed hawk is one of three species colloquially known in the United States as the "
chickenhawk", though it rarely preys on standard-sized chickens. The bird is sometimes also referred to as the red-tail for short, when the meaning is clear in context. Red-tailed hawks can acclimate to all the
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
s within their range, occurring on the edges of non-ideal habitats such as dense forests and sandy deserts.
[Preston, C. R. (2000). ''Red-tailed Hawk''. Stackpole Books.] The red-tailed hawk occupies a wide range of habitats and altitudes, including
desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...
s,
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 (from small
meadow
A meadow ( ) is an open habitat, or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as these areas maintain an open character. Meadows may be naturally occurring or artifi ...
s to the treed fringes of more extensive
prairie
Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the ...
s),
coniferous
Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extant ...
and
deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
forests,
agricultural fields, and
urban areas
An urban area, built-up area or urban agglomeration is a human settlement with a high population density and infrastructure of built environment. Urban areas are created through urbanization and are categorized by urban morphology as cities, t ...
. Its latitudinal limits fall around the
tree line
The tree line is the edge of the habitat at which trees are capable of growing. It is found at high elevations and high latitudes. Beyond the tree line, trees cannot tolerate the environmental conditions (usually cold temperatures, extreme snowp ...
in the
subarctic
The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of humid continental regions and covering much of Alaska, Canada, Iceland, the north of Scandinavia, Siberia, and the Cairngorms. Generally, ...
and it is absent from the high
Arctic
The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...
. Generally it favors varied habitats with
open woodland
Open or OPEN may refer to:
Music
* Open (band), Australian pop/rock band
* The Open (band), English indie rock band
* ''Open'' (Blues Image album), 1969
* ''Open'' (Gotthard album), 1999
* ''Open'' (Cowboy Junkies album), 2001
* ''Open'' (YF ...
,
woodland edge
A woodland edge or forest edge is the transition zone (ecotone) from an area of woodland or forest to fields or other open spaces. Certain species of plants and animals are adapted to the forest edge, and these species are often more familiar to hu ...
and
open terrain
Open terrain, open country or open ground is terrain which is mostly flat and free of obstructions such as trees and buildings. Examples include farmland, grassland and specially cleared areas such as an airport.
Such terrain is significant in ...
. It is legally protected in Canada,
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, and the United States by the
Migratory Bird Treaty Act
The Migratory Bird Treaty Act of 1918 (MBTA), codified at (although §709 is omitted), is a United States federal law, first enacted in 1918 to implement the convention for the protection of migratory birds between the United States and Canada . ...
.
The
14 recognized subspecies vary in appearance and range, varying most often in color, and in the west of North America, red-tails are particularly often strongly
polymorphic, with individuals ranging from almost white to nearly all black.
[Palmer, R. S., ed. (1988). ''Handbook of North American birds. Volume 5 Diurnal Raptors (part 2)''.] The subspecies
Harlan's hawk
Harlan's hawk or Harlan's red-tailed hawk (''Buteo jamaicensis harlani'') Website based on / supplement to book, is a subspecies of the red-tailed hawk.
Description
While similar in linear dimensions to the western red-tailed hawk (''B. j. cal ...
(''B. j. harlani'') is sometimes considered a separate species (''B. harlani'').
The red-tailed hawk is one of the largest members of the genus ''Buteo'', typically weighing from and measuring in length, with a wingspan from . This species displays
sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
in size, with females averaging about 25% heavier than males.
[
The diet of red-tailed hawks is highly variable and reflects their status as opportunistic generalists, but in North America, they are most often predators of 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 such as rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
s of an immense diversity of families and species. Prey that is terrestrial and at least partially diurnal is preferred, so types 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 are preferred where they naturally occur. Over much of the range, smallish rodents 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 alternated with larger rabbits and hares often collectively form the bulk of the diet. Large numbers of 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 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 can occur in the diet in several areas, and can even be the primary foods. Meanwhile, amphibian
Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...
s, 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 ...
and invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s can seem rare in the hawk’s regular diet, but they are not infrequently taken by immature hawks. Red-tailed hawks may survive on islands absent of native mammals on diets variously including invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s such as crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...
s, as well as 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 or birds. Like many ''Buteo'' species, they hunt from a perch most often, but can vary their hunting techniques where prey and habitat demand it.[Preston, C. R. and R. D. Beane. (2009). "Red-tailed Hawk (''Buteo jamaicensis''), ''The Birds of North America''. .] Because they are so common and easily trained as capable hunters, in the United States they are the most commonly captured hawks for falconry
Falconry is the hunting of wild animals in their natural state and habitat by means of a trained bird of prey. Small animals are hunted; squirrels and rabbits often fall prey to these birds. Two traditional terms are used to describe a person ...
. Falconers are permitted to take only passage hawks (which have left the nest, are on their own, but are less than a year old) so as to not affect the breeding population. Adults, which may be breeding or rearing chicks, may not be taken for falconry purposes, and doing so is illegal. Passage red-tailed hawks are also preferred by falconers because these younger birds have not yet developed the adult behaviors that would make them more difficult to train.[Beebe, F. L. (1976). ''North American Falconry and Hunting Hawks''. Hancock House Books (British Columbia).]
Taxonomy
The red-tailed hawk was formally described in 1788 by German naturalist Johann Friedrich Gmelin
, fields =
, workplaces = University of GöttingenUniversity of Tübingen
, alma_mater = University of Tübingen
, doctoral_advisor = Philipp Friedrich GmelinFerdinand Christoph Oetinger
, academic_advisors =
, doctora ...
under the binomial name
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
''Falco jamaicensis''. Gmelin based his description on the "cream-coloured buzzard" described in 1781 by John Latham in his ''A General Synopsis of Birds''. The type locality is Jamaica. The red-tailed hawk is now placed in the genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Buteo'' that was erected by French naturalist Bernard Germain de Lacépède
Bernard-Germain-Étienne de La Ville-sur-Illon, comte de Lacépède or La Cépède (; 26 December 17566 October 1825) was a French naturalist and an active freemason. He is known for his contribution to the Comte de Buffon's great work, the ...
in 1799.
The red-tailed hawk is a member of the subfamily Buteoninae
The Buteoninae are a subfamily of birds of prey which consists of medium to large, broad-winged species.
They have large, powerful, hooked beaks for tearing flesh from their prey, strong legs, and powerful talons. They also have extremely keen e ...
, which includes about 55 currently recognized species.[ Unlike many lineages of accipitrids, which seemed to have radiated out of Africa or south Asia, the Buteoninae clearly originated in the Americas based on fossil records and current species distributions (more than 75% of the extant hawks from this lineage are found in the Americas).][ As a subfamily, the Buteoninae seem to be rather old based on genetic materials, with ]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 ...
genera bearing several million years of individual evolution. Diverse in plumage appearance, habitat, prey, and nesting preferences, buteonine hawks are nonetheless typically medium- to large-sized hawks with ample wings (while some fossil forms are very large, larger than any eagle alive today). The red-tailed hawk is a member of the genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Buteo'', a group of medium-sized raptors with robust bodies and broad wings. Members of this genus are known as "buzzards" in Eurasia, but "hawks" in North America. Under current classification, the genus includes about 29 species, the second-most diverse of all extant accipitrid genera behind only ''Accipiter
''Accipiter'' is a genus of Bird of prey, birds of prey in the family Accipitridae. With 51 recognized species it is the most diverse genus in its family. Most species are called goshawks or sparrowhawks, although almost all New World species (ex ...
''.[ The buzzards of Eurasia and Africa are mostly part of the genus ''Buteo'', although two other small genera within the subfamily Buteoninae occur in Africa.]
At one time, the rufous-tailed hawk
The rufous-tailed hawk (''Buteo ventralis'') is a species of bird of prey in the family Accipitridae.
The rufous-tailed hawk is found in southern Argentina and Chile, including the entire region of Tierra del Fuego. Its natural habitats are temp ...
(''B. ventralis''), distributed in Patagonia
Patagonia () refers to a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and gl ...
and some other areas of southern South America, was considered part of the red-tailed hawk species. With a massive distributional gap consisting of most of South America, the rufous-tailed hawk is considered a separate species now, but the two hawks still compromise a "species pair" or superspecies, as they are clearly closely related. The rufous-tailed hawk, while comparatively little studied, is very similar to the red-tailed hawk, being about the same size and possessing the same wing structure, and having more or less parallel nesting and hunting habits. Physically, however, rufous-tailed hawk adults do not attain a bright brick-red tail as do red-tailed hawks, instead retaining a dark brownish-cinnamon tail with many blackish crossbars similar to juvenile red-tailed hawks.[ Another, more well-known, close relative to the red-tailed hawk is 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 ...
(''B. buteo''), which has been considered as its Eurasian " broad ecological counterpart" and may also be within a species complex with red-tailed hawks. The common buzzard, in turn, is also part of a species complex with other Old World buzzards, namely the mountain buzzard
The mountain buzzard (''Buteo oreophilus'') is a bird of prey that lives in montane forests in East Africa, it and the forest buzzard (''Buteo trizonatus'') of southern Africa were, until recently, considered to be a single species.
Description
...
(''B. oreophilus''), the forest buzzard
The forest buzzard (''Buteo trizonatus''), is a species of bird of prey found in Africa, though some authorities have placed it as a subspecies of another species, the mountain buzzard, ''Buto oreophilus''. This is a resident breeding species in ...
(''B. trizonatus'' ), and the Madagascar buzzard
The Madagascar buzzard (''Buteo brachypterus'') is a bird of prey which is endemic to Madagascar. It is a species from the widespread genus ''Buteo'' in the family ''Accipitridae''.
Description
The Madagascar buzzard is a typical old-world buzza ...
(''B. brachypterus'').[ All six species, although varying notably in size and plumage characteristics, in the alleged species complex that contains the red-tailed hawk share with it the feature of the blackish patagium marking, which is missing in most other ''Buteo'' spp.][
]
Subspecies
At least 14 recognized subspecies of ''B. jamaicensis'' are described, which vary in range and in coloration. Not all authors accept every subspecies, though, particularly some of the insular races of the tropics (which differ only slightly in some cases from the nearest mainland forms) and particularly Krider's hawk, by far the most controversial red-tailed hawk race, as few authors agree on its suitability as a full-fledged subspecies.[
]
Description
Red-tailed hawk plumage
Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
can be variable, depending on the subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
and the region. These color variations are morphs, and are not related to molt
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...
ing. The western North American population, ''B. j. calurus'', is the most variable subspecies and has three main color morphs: light, dark, and intermediate or rufous. The dark and intermediate morphs constitute 10–20% of the population in the Western United States, but seem to constitute only 1–2% of ''B. j. calurus'' in western Canada.[Clark, W.S. (2014)]
HARLAN’S HAWK differs from RED-TAILED HAWK
Global Raptor Information Network. A whitish underbelly with a dark brown band across the belly, formed by horizontal streaks in feather
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier ...
patterning, is present in most color variations. This feature is variable in eastern hawks and generally absent in some light subspecies (i.e. ''B. j. fuertesi'').[ Most adult red-tails have a dark-brown nape and upper head, which gives them a somewhat hooded appearance, while the throat can variably present a lighter brown "necklace". Especially in younger birds, the underside may be otherwise covered with dark-brown spotting, and some adults may too manifest this stippling. The back is usually a slightly darker brown than elsewhere with paler scapular feathers, ranging from tawny to white, forming a variable imperfect "V" on the back. The tail of most adults, which gives this species its name, is rufous brick-red above with a variably sized, black subterminal band and generally appears light buff-orange from below. In comparison, the typical pale immatures (i.e. less than two years old) typically have a mildly paler headed and tend to show a darker back than adults with more apparent pale wing-feather edges above (for descriptions of dark morph juveniles from ''B. j. calurus'', which is also generally apt for description of rare dark morphs of other races, see under that subspecies description). In immature red-tailed hawks of all morphs, the tail is a light brown above with numerous small dark brown bars of roughly equal width, but these tend to be much broader on dark morph birds. Even in young red-tails, the tail may be a somewhat rufous tinge of brown.] The 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 ...
is relatively short and dark, in the hooked shape characteristic of raptors, and the head can sometimes appear small in size against the thick body frame. The cere
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, ...
, the legs, and the feet of the red-tailed hawk are all yellow, as is the color of bare parts in many accipitrids of different lineages. Immature birds can be readily identified at close range by their yellowish irises. As the bird attains full maturity over the course of 3–4 years, the iris slowly darkens into a reddish-brown, which is the adult eye-color in all races. Seen in flight, adults usually have dark brown along the lower edge of the wings, against a mostly pale wing, which bares light brownish barring. Individually, the underwing coverts can range from all dark to off-whitish (most often more heavily streaked with brown) which contrasts with a distinctive black patagium
The patagium (plural: patagia) is a membranous body part that assists an animal in obtaining lift when gliding or flight. The structure is found in extant and extinct groups of flying and gliding animals including bats, birds, some dromaeosaurs ...
marking. The wing coloring of adults and immatures is similar but for typical pale morph immatures having somewhat heavier brownish markings.[Brown, Leslie and Amadon, Dean (1986) ''Eagles, Hawks and Falcons of the World''. The Wellfleet Press. .]
Though the markings and color vary across the subspecies, the basic appearance of the red-tailed hawk is relatively consistent.
Overall, this species is blocky and broad in shape, often appearing (and being) heavier than other ''Buteo
''Buteo'' is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in the New World (Etymology: ''Buteo'' is the Latin name o ...
s'' of similar length. They are the heaviest ''Buteos'' on average in eastern North America, albeit scarcely ahead of the larger winged rough-legged buzzard
The rough-legged buzzard or rough-legged hawk (''Buteo lagopus'') is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It ...
(''Buteo lagopus''), and second only in size in the west to the ferruginous hawk
The ferruginous hawk, (''Buteo regalis''), is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name is ferrugineous rough-leg, due to its similarity to the closely related rough-legged hawk (''B. lagopus'').
...
(''Buteo regalis''). Red-tailed hawks may be anywhere from the fifth to the ninth heaviest ''Buteo'' in the world depending on what figures are used. However, in the northwestern United States, ferruginous hawk females are 35% heavier than female red-tails from the same area. On average, western red-tailed hawks are relatively longer winged and lankier proportioned but are slightly less stocky, compact and heavy than eastern red-tailed hawks in North America. Eastern hawks may also have mildly larger talons and bills than western ones. Based on comparisons of morphology and function amongst all accipitrids, these features imply that western red-tails may need to vary their hunting more frequently to on the wing as the habitat diversifies to more open situations and presumably would hunt more variable and faster prey, whereas the birds of the east, which was historically well-wooded, are more dedicated perch hunters and can take somewhat larger prey but are likely more dedicated mammal hunters. In terms of size variation, red-tailed hawks run almost contrary to Bergmann's rule
Bergmann's rule is an ecogeographical rule that states that within a broadly distributed taxonomic clade, populations and species of larger size are found in colder environments, while populations and species of smaller size are found in warmer ...
(i.e. that northern animals should be larger in relation than those closer to the Equator
The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can als ...
within a species) as one of the northernmost subspecies, ''B. j. alascensis'', is the second smallest race based on linear dimensions and that two of the most southerly occurring races in the United States, ''B. j. fuertesi'' and ''B. j. umbrinus'', respectively, are the largest proportioned of all red-tailed hawks.[ Red-tailed hawks tend have a relatively short but broad tails and thick, chunky wings.] Although often described as long-winged,[ the proportional size of the wings is quite small and red-tails have high ]wing loading
In aerodynamics, wing loading is the total mass of an aircraft or flying animal divided by the area of its wing. The stalling speed of an aircraft in straight, level flight is partly determined by its wing loading. An aircraft or animal with a ...
for a buteonine hawk. For comparison, two other widespread ''Buteo'' hawks in North America were found to weigh: for every square centimeter of wing area in the rough-legged buzzard
The rough-legged buzzard or rough-legged hawk (''Buteo lagopus'') is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It ...
(''B. lagopus'') and /cm2 in the red-shouldered hawk
The red-shouldered hawk (''Buteo lineatus'') is a medium-sized buteo. Its breeding range spans eastern North America and along the coast of California and northern to northeastern-central Mexico. It is a permanent resident throughout most of its ...
(''B. lineatus''). In contrast, the red-tailed hawk weighed considerably more for their wing area: per square cm.
As is the case with many raptors, the red-tailed hawk displays sexual dimorphism in size, as females are on average 25% larger than males. As is typical in large raptors, frequently reported mean body mass for red-tailed hawks is somewhat higher than expansive research reveals. Part of this weight variation is seasonal fluctuations; hawks tend to be heavier in winter than during migration or especially during the trying summer breeding season, and also due to clinal variation. Furthermore, immature hawks are usually lighter in mass than their adult counterparts despite having somewhat longer wings and tails. Male red-tailed hawks may weigh from and females may weigh (the lowest figure from a migrating female immature from Goshute Mountains
The Goshute Mountains is a mountain range in southeastern Elko County, Nevada, United States.
Description
The range is separated from the Toano Range to the north by Morgan Pass.
The range was named after the Goshute Indians.
See also
* List ...
, Nevada
Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...
, the highest from a wintering female in Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...
). Some sources claim the largest females can weigh up to , but whether this is in reference to wild hawks (as opposed to those in captivity or used for falconry) is not clear. The largest known survey of body mass in red-tailed hawks is still credited to Craighead and Craighead (1956), who found 100 males to average and 108 females to average . However, these figures were apparently taken from labels on museum specimens, from natural history collections in Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...
and Pennsylvania
Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...
, without note to the region, age, or subspecies of the specimens.[Craighead, J. J. and F. C. Craighead, Jr. (1956). ''Hawks, owls and wildlife''. Stackpole Co. Harrisburg, PA.] However, 16 sources ranging in sample size from the aforementioned 208 specimens to only four hawks in Puerto Rico
Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...
(with 9 of the 16 studies of migrating red-tails), showed that males weigh a mean of and females weigh a mean of , about 15% lighter than prior species-wide published weights. Within the continental United States
The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii ...
, typical weights of males can range from (for migrating males in Chelan County, Washington
Chelan County (, ) is a List of counties in Washington, county in the U.S. state of Washington (state), Washington. As of the 2020 United States census, 2020 census, its population was 79,074. The county seat and largest city is Wenatchee, Washi ...
) to (for male hawks found dead in ), and females ranged from (migrants in the Goshutes) to (for females diagnosed as ''B. j. borealis'' in western Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
).[Snyder, N. F. R. and Wiley, J. W. (1976)]
"Sexual size dimorphism in hawks and owls of North America"
''Ornithological Monographs'', Vol. 20, pp. i–vi, 1–96. Size variation in body mass reveals that the red-tailed hawk typically varies only a modest amount and that size differences are geographically inconsistent.[
Male red-tailed hawks can measure in total length, females measuring long. Their wingspan typically can range from , although the largest females may possible span up to . In the standard scientific method of measuring wing size, the wing chord is long. The tail measures in length.][ The exposed culmen was reported to range from and the tarsus averaged across the races.][ The middle toe (excluding talon) can range from , with the hallux-claw (the talon of the rear toe, which has evolved to be the largest in accipitrids) measuring from in length.][
]
Identification
Although they overlap in range with most other American diurnal raptors, identifying most mature red-tailed hawks to species is relatively straightforward, particularly if viewing a typical adult at a reasonable distance. The red-tailed hawk is the only North American hawk with a rufous tail and a blackish patagium
The patagium (plural: patagia) is a membranous body part that assists an animal in obtaining lift when gliding or flight. The structure is found in extant and extinct groups of flying and gliding animals including bats, birds, some dromaeosaurs ...
marking on the leading edge of its wing (which is obscured only on dark morph adults and Harlan’s hawks by similarly dark-colored feathers).[ Other larger adult ''Buteo'' spp. in North America usually have obvious distinct markings that are absent in red-tails, whether the rufous-brown "beard" of ]Swainson's hawk
Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond ...
s (''B. swainsonii'') or the colorful rufous belly and shoulder markings and striking black-and-white mantle of red-shouldered hawk
The red-shouldered hawk (''Buteo lineatus'') is a medium-sized buteo. Its breeding range spans eastern North America and along the coast of California and northern to northeastern-central Mexico. It is a permanent resident throughout most of its ...
s (also the small "windows" seen at the end of their primaries).[Robbins, C. S., Bruun, B., & Zim, H. S. (2001). ''Birds of North America: A Guide to Field Identification''. Macmillan.] In perched individuals, even as silhouettes, the shape of large ''Buteo'' spp. may be distinctive, such as the wingtips overhanging the tail in several other species, but not in red-tails. North American ''Buteo'' spp. range from the dainty, compact builds of much smaller ones, such as broad-winged hawk
The broad-winged hawk (''Buteo platypterus'') is a medium-sized hawk of the genus ''Buteo''. During the summer, some subspecies are distributed over eastern North America, as far west as British Columbia and Texas; they then migrate south to wi ...
(''B. platypterus'') to the heavyset, neckless look of ferruginous hawk
The ferruginous hawk, (''Buteo regalis''), is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name is ferrugineous rough-leg, due to its similarity to the closely related rough-legged hawk (''B. lagopus'').
...
s or the rough-legged buzzard
The rough-legged buzzard or rough-legged hawk (''Buteo lagopus'') is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It ...
s, which have a compact, smaller appearance than a red-tail in perched birds due to its small bill, short neck, and much shorter tarsi, while the opposite effect occurs in flying rough-legs with their much bigger wing area.[ In flight, most other large North American ''Buteo'' spp. are distinctly longer and more slender-winged than red-tailed hawks, with the much paler ferruginous hawk having peculiarly slender wings in relation to its massive, chunky body. Swainson's hawks are distinctly darker on the wing and ferruginous hawks are much paler-winged than typical red-tailed hawks. Pale morph adult ferruginous hawk can show mildly tawny-pink (but never truly rufous) upper tail, and like red-tails tend to have dark markings on underwing-coverts and can have a dark belly band, but compared to red-tailed hawks have a distinctly broader head, their ]remiges
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 ...
are much whiter looking with very small, dark primary tips, they lack the red-tail's diagnostic patagial marks and usually also lack the dark subterminal tail-band, and ferruginous hawks have totally feathered tarsi. With its whitish head, the ferruginous hawk is most similar to Krider's red-tailed hawks, especially in immature plumage, but the larger hawk has broader head and narrower wing shape, and the ferruginous immatures are paler underneath and on their legs. Several species share a belly band with the typical red-tailed hawk, but they vary from subtle (as in the ferruginous hawk) to solid blackish, the latter in most light-morph rough-legged buzzard
The rough-legged buzzard or rough-legged hawk (''Buteo lagopus'') is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It ...
s.[ More difficult to identify among adult red-tails are their darkest variations, as most species of ''Buteo'' in North America also have dark morphs. Western dark morph red-tails (i.e. ''B. j. calurus'') adults, however, retain the typical distinctive brick-red tail, which other species lack, and may stand out even more against the otherwise all chocolate-brown to black bird. Standard pale juveniles when perched show a whitish patch in the outer half of the upper surface of the wing, which other juvenile ''Buteo'' spp. lack.][ The most difficult to identify stages and plumage types are dark morph juveniles, Harlan's hawk and some Krider's hawks (the latter mainly with typical ferruginous hawks as mentioned). Some darker juveniles are similar enough to other ''Buteo'' juveniles that they "cannot be identified to species with any confidence under various field conditions."][ However, field identification techniques have advanced in the last few decades and most experienced hawk-watchers can distinguish even the most vexingly plumaged immature hawks, especially as the wing shapes of each species becomes apparent after seeing many. Harlan’s hawks are most similar to dark morph ]rough-legged buzzard
The rough-legged buzzard or rough-legged hawk (''Buteo lagopus'') is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It ...
s and dark morph ferruginous hawk
The ferruginous hawk, (''Buteo regalis''), is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name is ferrugineous rough-leg, due to its similarity to the closely related rough-legged hawk (''B. lagopus'').
...
s. Wing shape is the most reliable identification tool for distinguishing Harlan's hawks from these, but also the pale streaking on the breast of Harlan's, which tends to be conspicuous in most individuals, and is lacking in the other hawks. Also, dark morph ferruginous hawks do not have the dark subterminal band of a Harlan's hawk, but do bear a black undertail covert lacking in Harlan's.
Vocalization
The cry of the red-tailed hawk is a 2- to 3-second, hoarse, rasping scream, variously transcribed as ''kree-eee-ar'', ''tsee-eeee-arrr'' or ''sheeeeee'', that begins at a high pitch and slurs downward. This cry is often described as sounding similar to a steam whistle.[ The red-tailed hawk frequently vocalizes while hunting or soaring, but vocalizes loudest and most persistently in defiance or anger, in response to a predator or a rival hawk's intrusion into its territory.] At close range, it makes a croaking ''guh-runk'', possibly as a warning sound. Nestlings may give peeping notes with a "soft, sleepy quality" that give way to occasional screams as they develop, but those are more likely to be a soft whistle rather than the harsh screams of the adults. Their latter hunger call, given from 11 days (as recorded in Alaska) to after fledgling (in California), is different, a two-syllabled, wailing ''klee-uk'' food cry exerted by the young when parents leave the nest or enter their field of vision. A strange mechanical sound "not very unlike the rush of distant water" has been reported as uttered in the midst of a sky-dance.[ A modified call of ''chirp-chwirk'' is given during courtship, while a low key, duck-like nasal ''gank'' may be given by pairs when they are relaxed.][
The fierce, screaming cry of the adult red-tailed hawk is frequently used as a generic raptor sound effect in television shows and other media, even if the bird featured is not a red-tailed hawk.] It is especially used in depictions of the bald eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as ...
, which contributes to the common misconception
Each entry on this list of common misconceptions is worded as a correction; the misconceptions themselves are implied rather than stated. These entries are concise summaries of the main subject articles, which can be consulted for more detail.
...
that it is a bald eagle cry; actual bald eagle vocalizations are far softer and more chirpy than those of a red-tailed hawk.
Distribution and habitat
The red-tailed hawk is one of the most widely distributed of all raptors in the Americas. It occupies the largest breeding range of any diurnal raptor north of the Mexican border, just ahead of the American kestrel
The American kestrel (''Falco sparverius''), also called the sparrow hawk, is the smallest and most common falcon in North America. It has a roughly two-to-one range in size over subspecies and sex, varying in size from about the weight of ...
(''Falco sparverius''). While the peregrine falcon
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a Cosmopolitan distribution, cosmopolitan bird of prey (Bird of prey, raptor) in the family (biology), family Falco ...
(''Falco peregrinus'') has a greater latitudinal distribution as a nester in North America, its range as a breeding species is far more sporadic and sparse than that of red-tailed hawks.[American Ornithologists' Union. 1998a. ''Check-list of North American birds. 7th edition ed''. Washington, D.C.: American Ornithologists' Union.] The red-tailed hawk breeds from nearly north-central Alaska, the Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
, and a considerable portion of the Northwest Territories
The Northwest Territories (abbreviated ''NT'' or ''NWT''; french: Territoires du Nord-Ouest, formerly ''North-Western Territory'' and ''North-West Territories'' and namely shortened as ''Northwest Territory'') is a federal territory of Canada. ...
, there reaching as far as a breeder as Inuvik
Inuvik (''place of man'') is the only town in the Inuvik Region, and the third largest community in Canada's Northwest Territories. Located in what is sometimes called the Beaufort Delta Region, it serves as its administrative and service cen ...
, Mackenzie River Delta and skirting the southern shores of Great Bear Lake
Great Bear Lake ( den, Sahtú; french: Grand lac de l'Ours) is a lake in the boreal forest of Canada. It is the largest lake entirely in Canada (Lake Superior and Lake Huron are larger but straddle the Canada–US border), the fourth-largest ...
and Great Slave Lake
Great Slave Lake (french: Grand lac des Esclaves), known traditionally as Tıdeè in Tłı̨chǫ Yatıì (Dogrib), Tinde’e in Wıìlıìdeh Yatii / Tetsǫ́t’ıné Yatıé (Dogrib / Chipewyan), Tu Nedhé in Dëne Sųłıné Yatıé (Chi ...
. Thereafter in northern Canada, breeding red-tails continue to northern Saskatchewan
Saskatchewan ( ; ) is a Provinces and territories of Canada, province in Western Canada, western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on t ...
and across to north-central Ontario east to central Quebec and the Maritime Provinces
The Maritimes, also called the Maritime provinces, is a region of Eastern Canada consisting of three provinces: New Brunswick, Nova Scotia, and Prince Edward Island. The Maritimes had a population of 1,899,324 in 2021, which makes up 5.1% of Ca ...
of Canada, and south continuously to Florida. No substantial gaps occur throughout the entire contiguous United States, where breeding red-tailed hawks do not occur. Along the Pacific, their range includes all of Baja California
Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
, including Islas Marías
The Islas Marías ("Mary Islands") are an archipelago of four islands that belong to Mexico. They are located in the Pacific Ocean, some off the coast of the mexican state, state of Nayarit and about southeast of the tip of Baja California. The ...
, and Socorro Island
Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest ...
in the Revillagigedo Islands
The Revillagigedo Islands ( es, Islas Revillagigedo, ) or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem. They lie approximately from Socorro Island south and southwest of C ...
. On the mainland, breeding red-tails are found continuously to Oaxaca
Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...
, then experience a brief gap at the Isthmus of Tehuantepec
The Isthmus of Tehuantepec () is an isthmus in Mexico. It represents the shortest distance between the Gulf of Mexico and the Pacific Ocean. Before the opening of the Panama Canal, it was a major overland transport route known simply as the Te ...
thereafter subsequently continuing from Chiapas through central Guatemala on to northern Nicaragua. To the south, the population in highlands from Costa Rica to central Panama is isolated from breeding birds in Nicaragua. Further east, breeding red-tailed hawks occur in the West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greater A ...
in north Bahamas
The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to ...
(i.e. Grand Bahama
Grand Bahama is the northernmost of the islands of the Bahamas, with the town of West End located east of Palm Beach, Florida. It is the third largest island in the Bahamas island chain of approximately 700 islands and 2,400 cays. The island is ...
, Abaco and Andros
Andros ( el, Άνδρος, ) is the northernmost island of the Greek Cyclades archipelago, about southeast of Euboea, and about north of Tinos. It is nearly long, and its greatest breadth is . It is for the most part mountainous, with many fr ...
) and all larger islands (such as Cuba, Jamaica, Hispaniola, and Puerto Rico) and into the northern Lesser Antilles
The Lesser Antilles ( es, link=no, Antillas Menores; french: link=no, Petites Antilles; pap, Antias Menor; nl, Kleine Antillen) are a group of islands in the Caribbean Sea. Most of them are part of a long, partially volcanic island arc betwe ...
(Virgin Islands
The Virgin Islands ( es, Islas Vírgenes) are an archipelago in the Caribbean Sea. They are geologically and biogeographically the easternmost part of the Greater Antilles, the northern islands belonging to the Puerto Rico Trench and St. Croix ...
, Saint Barthélemy
Saint Barthélemy (french: Saint-Barthélemy, ), officially the Collectivité territoriale de Saint-Barthélemy, is an overseas collectivity of France in the Caribbean. It is often abbreviated to St. Barth in French, and St. Barts in English ...
, Saba Saba may refer to:
Places
* Saba (island), an island of the Netherlands located in the Caribbean Sea
* Şaba (Romanian for Shabo), a town of the Odesa Oblast, Ukraine
* Sabá, a municipality in the department of Colón, Honduras
* Saba (river), L ...
, Saint Kitts
Saint Kitts, officially the Saint Christopher Island, is an island in the West Indies. The west side of the island borders the Caribbean Sea, and the eastern coast faces the Atlantic Ocean. Saint Kitts and the neighbouring island of Nevis cons ...
, and Nevis
Nevis is a small island in the Caribbean Sea that forms part of the inner arc of the Leeward Islands chain of the West Indies. Nevis and the neighbouring island of Saint Kitts constitute one country: the Federation of Saint Kitts and Ne ...
, being rare as a resident on Saint Eustatius
Sint Eustatius (, ), also known locally as Statia (), is an island in the Caribbean. It is a Caribbean Netherlands, special municipality (officially "Public body (Netherlands), public body") of the Netherlands.
The island lies in the northern ...
and are probably extinct on Saint Martin). Their typical winter range stretches from southern Canada south throughout the remainder of the breeding range.[
Red-tailed hawks have shown the ability to become habituated to almost any habitat present in North and Central America. Their preferred habitat is mixed forest and ]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 ...
, largely woodland edge
A woodland edge or forest edge is the transition zone (ecotone) from an area of woodland or forest to fields or other open spaces. Certain species of plants and animals are adapted to the forest edge, and these species are often more familiar to hu ...
with tall 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 or alternately high bluffs that may be used as nesting and perching sites. They occupy a wide range of habitats and altitudes, including desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...
s, 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, nearly any coast
The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...
al or 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 ...
habitat, mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and ...
s, foothill
Foothills or piedmont are geographically defined as gradual increases in elevation at the base of a mountain range, higher hill range or an upland area. They are a transition zone between plains and low relief hills and the adjacent topograp ...
s, coniferous
Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extant ...
and deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
woodland
A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...
s, and tropical rainforest
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatori ...
s. Agricultural fields and pastures
Pasture (from the Latin ''pastus'', past participle of ''pascere'', "to feed") is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep, or swine ...
, which are more often than not varied with groves, ridges, or streamside trees in most parts of America, may make nearly ideal habitat for breeding or wintering red-tails. They also adapt well to suburban
A suburb (more broadly suburban area) is an area within a metropolitan area, which may include commercial and mixed-use, that is primarily a residential area. A suburb can exist either as part of a larger city/urban area or as a separate ...
areas especially ones with tall trees or any kind of parkland.[ Some red-tails may survive or even flourish in urban areas, usually hunting and roosting in available urban ]park
A park is an area of natural, semi-natural or planted space set aside for human enjoyment and recreation or for the protection of wildlife or natural habitats. Urban parks are urban green space, green spaces set aside for recreation inside t ...
s, cemeteries
A cemetery, burial ground, gravesite or graveyard is a place where the remains of dead people are buried or otherwise interred. The word ''cemetery'' (from Greek , "sleeping place") implies that the land is specifically designated as a buri ...
, road verge
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
s, and so on, and nesting freely either in trees or virtually any tall man-made structures. One famous urban red-tailed hawk, known as "Pale Male
Pale may refer to:
Jurisdictions
* Medieval areas of English conquest:
** Pale of Calais, in France (1360–1558)
** The Pale, or the English Pale, in Ireland
*Pale of Settlement, area of permitted Jewish settlement, western Russian Empire (179 ...
", became the subject of a nonfiction book, ''Red-Tails in Love: A Wildlife Drama in Central Park'', and is the first known red-tail in decades to successfully nest and raise young in the crowded New York City borough of Manhattan
Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the original counties of the U.S. state ...
.[Winn, M. 1999. ''Red-tails in love. A Wildlife Drama in Central Park''. New York, NY: Vintage Departures, Vintage Books, Random Haouse, Inc.] As studied in Syracuse, New York
Syracuse ( ) is a City (New York), city in and the county seat of Onondaga County, New York, Onondaga County, New York, United States. It is the fifth-most populous city in the state of New York following New York City, Buffalo, New York, Buffa ...
, the highway system has been very beneficial to red-tails as it juxtaposed trees and open areas and blocks human encroachment with fences, with the red-tailed hawks easily becoming acclimated to car traffic. The only practice that has a negative effect on the highway-occupying red-tails is the planting of exotic
Exotic may refer to:
Mathematics and physics
* Exotic R4, a differentiable 4-manifold, homeomorphic but not diffeomorphic to the Euclidean space R4
* Exotic sphere, a differentiable ''n''-manifold, homeomorphic but not diffeomorphic to the ordina ...
''Phragmites
''Phragmites'' () is a genus of four species of large perennial reed grasses found in wetlands throughout temperate and tropical regions of the world.
Taxonomy
The World Checklist of Selected Plant Families, maintained by Kew Garden in London ...
'', which may occasionally obscure otherwise ideal highway habitat.
In the northern Great Plains
The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...
, the widespread practices of wildfire suppression
Wildfire suppression is a range of firefighting tactics used to suppress wildfires. Firefighting efforts in wild land areas require different techniques, equipment, and training from the more familiar structure fire fighting found in populated ...
and planting of exotic trees by humans has allowed groves of aspen
Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the ''Populus'' genus.
Species
These species are called aspens:
*'' Populus adenopoda'' – Chinese aspen (China ...
and various other trees to invade what was once vast, almost continuous prairie grasslands, causing grassland obligates such as ferruginous hawks to decline and allowing parkland-favoring red-tails to flourish. To the contrary, clear-cutting of mature woodlands in New England
New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian provinces ...
, resulting in only fragmented and isolated stands of trees or low second growth remaining, was recorded to also benefit red-tailed hawks, despite being to the determent of breeding red-shouldered hawk
The red-shouldered hawk (''Buteo lineatus'') is a medium-sized buteo. Its breeding range spans eastern North America and along the coast of California and northern to northeastern-central Mexico. It is a permanent resident throughout most of its ...
s.[Bent, A. C. 1938. ''Life histories of North American birds of prey, Part 1''. U.S. National Museum Bulletin 170:295–357.] The red-tailed hawk, as a whole, rivals the peregrine falcon and the great horned owl among raptorial birds in the use of diverse habitats in North America. Beyond the high Arctic
High may refer to:
Science and technology
* Height
* High (atmospheric), a high-pressure area
* High (computability), a quality of a Turing degree, in computability theory
* High (tectonics), in geology an area where relative tectonic uplift to ...
(as they discontinue as a breeder at the tree line), few other areas exist where red-tailed hawks are absent or rare in North and Central America. Some areas of unbroken forest, especially lowland tropical forests, rarely host red-tailed hawks, although they can occupy forested tropical highlands surprisingly well. In deserts, they can only occur where some variety of arborescent growth or ample rocky bluffs or canyon
A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tenden ...
s occur.
Behavior
The red-tailed hawk is highly conspicuous to humans in much of its daily behavior. Most birds in resident populations, which are well more than half of all red-tailed hawks, usually split nonbreeding-season activity between territorial soaring flight and sitting on a perch. Often, perching is for hunting purposes, but many sit on a tree branch for hours, occasionally stretching on a single wing or leg to keep limber, with no signs of hunting intent.[ Wintering typical pale-morph hawks in ]Arkansas
Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage ...
were found to perch in open areas near the top of tall, isolated trees, whereas dark morphs more frequently perched in dense groups of trees.[ For many, and perhaps most, red-tailed hawks being mobbed by various birds is a daily concern and can effectively disrupt many of their daily behaviors. Mostly larger ]passerine
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by t ...
s, of multiple families from tyrant flycatcher
The tyrant flycatchers (Tyrannidae) are a family of passerine birds which occur throughout North and South America. They are considered the largest family of birds known to exist in the world, with more than 400 species. They are the most dive ...
s to icterid
Icterids () or New World blackbirds make up a family, the Icteridae (), of small to medium-sized, often colorful, New World passerine birds. Most species have black as a predominant plumage color, often enlivened by yellow, orange, or red. The ...
s, mob red-tails, despite other raptors, such as ''Accipiter'' hawks and falcons, being a notably greater danger to them. The most aggressive and dangerous attacker as such is likely to be various crow
A crow is a bird of the genus ''Corvus'', or more broadly a synonym for all of ''Corvus''. Crows are generally black in colour. The word "crow" is used as part of the common name of many species. The related term "raven" is not pinned scientifical ...
s or other 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, i.e. American crow
The American crow (''Corvus brachyrhynchos'') is a large passerine bird species of the family Corvidae. It is a common bird found throughout much of North America. American crows are the New World counterpart to the carrion crow of Europe and th ...
s (''Corvus brachyrhynchos''), because a mobbing group (or "murder") of them can number up to as many as 75 crows, which may cause grievous physical harm to a solitary hawk, and if the hawks are nesting, separate the parent hawks and endanger the eggs or nestlings within their nest to predation by crows. Birds that mob red-tailed hawks can tell how distended the hawk's crop is (i.e. the upper chest and throat area being puffy versus flat-feathered and sleek), thus mob more often when the hawk is presumably about to hunt.
Flight
In flight, this hawk soars with wings often in a slight dihedral, flapping as little as possible to conserve energy. Soaring is by far the most efficient method of flight for red-tailed hawks, so is used more often than not. Active flight is slow and deliberate, with deep wing beats. Wing beats are somewhat less rapid in active flight than in most other ''Buteo'' hawks, even heavier species such as ferruginous hawks tend to flap more swiftly, due to the morphology of the wings. In wind, it occasionally hovers on beating wings and remains stationary above the ground, but this flight method is rarely employed by this species. When soaring or flapping its wings, it typically travels from , but when diving may exceed . Although North American red-tailed hawks will occasionally hunt from flight, a great majority of flight by red-tails in this area is for non-hunting purpose.[ During nest defense, red-tailed hawks may be capable of surprisingly swift, vigorous flight, while repeatedly diving at perceived threats.]
Migration
Red-tailed hawks are considered partial migrants, as in about the northern third of their distribution, which is most of their range in Canada and Alaska, they almost entirely vacate their breeding grounds.[ In coastal areas of the north, however, such as in the ]Pacific Northwest
The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...
to southern Alaska and in Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland".
Most of the population are native Eng ...
on the Atlantic, red-tailed hawks do not usually migrate.[ More or less, any area where snow cover is nearly continuous during the winter shows an extended absence of most red-tailed hawks, so some areas as far south as Montana may show strong seasonal vacancies of red-tails.][ In southern Michigan, immature red-tailed hawks tended to remain in winter only when voles were abundant. During relatively long, harsh winters in Michigan, many more young ones were reported in northeastern Mexico.][ To the opposite extreme, hawks residing as far north as ]Fairbanks
Fairbanks is a home rule city and the borough seat of the Fairbanks North Star Borough in the U.S. state of Alaska. Fairbanks is the largest city in the Interior region of Alaska and the second largest in the state. The 2020 Census put the po ...
, Alaska, may persevere through the winter on their home territory, as was recorded with one male over three consecutive years.[Lowe, C. 1978. ''Certain life history aspects of the Red-tailed Hawk, central Oklahoma and interior Alaska''. Master's Thesis, Univ. Alaska, Fairbanks.] Birds of any age tend to be territorial during winter but may shift ranges whenever food requirements demand it.[ Wintering birds tend to perch on inconspicuous tree perches, seeking shelter especially if they have a full crop or are in the midst of poor or overly windy weather. Adult wintering red-tails tend to perch more prominently than immatures do, which select lower or more secluded perches. Immatures are often missed in winter bird counts, unless they are being displaced by dominant adults. Generally, though, immatures can seem to recognize that they are less likely to be attacked by adults during winter and can perch surprisingly close to them. Age is the most significant consideration of wintering hawks' hierarchy, but size does factor in, as larger immatures (presumably usually females) are less likely to displaced than smaller ones.][ Dark adult red-tailed hawks appear to be harder to locate when perched than other red-tails. In Oklahoma, for example, wintering adult Harlan's hawks were rarely engaged in fights or chased by other red-tails. These hawks tended to gather in regional pockets and frequently the same ones occurred year-to-year.][ In general, migratory behavior is complex and reliant on each individual hawk's decision-making (i.e. whether prey populations are sufficient to entice the hawk to endure prolonged snow cover).][ During fall migration, departure may occur as soon as late September, but peak movements occur in late October and all of November in the United States, with migration ceasing after mid-December. The northernmost migrants may pass over resident red-tailed hawks in the contiguous United States, while the latter are still in the midst of brooding fledglings.][ Not infrequently, several autumn hawk watches in Ontario, Quebec, and the northern United States record 4,500–8,900 red-tailed hawks migrating through each fall, with records of up to 15,000 in a season at Hawk Ridge hawk watch in ]Duluth, Minnesota
, settlement_type = City
, nicknames = Twin Ports (with Superior), Zenith City
, motto =
, image_skyline =
, image_caption = Clockwise from top: urban Duluth skyline; Minnesota ...
.[ Unlike some other ''Buteo'' spp., such as Swainson's hawks and broad-winged hawks, red-tailed hawks do not usually migrate in groups, instead passing by one-by-one, and only migrate on days when winds are favorable.][ Most migrants do not move past southern Mexico in late autumn, but a few North American migrants may annually move as far south as breeding red-tailed hawks happen to occur, i.e. in Central America to as far south Panama. However, a few records were reported of wintering migrant red-tails turning up in ]Colombia
Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...
, the first records of them anywhere in South America.[ Spring northward movements may commence as early as late February, with peak numbers usually occurring in late March and early April. Seasonal counts may include up to 19,000 red-tails in spring at Derby Hill hawk watch, in ]Oswego, New York
Oswego () is a city in Oswego County, New York, United States. The population was 16,921 at the 2020 census. Oswego is located on Lake Ontario in Upstate New York, about 35 miles (55km) northwest of Syracuse. It promotes itself as "The Port C ...
, sometimes more than 5,000 are recorded in a day there.[ The most northerly migratory individuals may not reach breeding grounds until June, even adults.][
Immature hawks migrate later than adults in spring on average, but not, generally speaking, in autumn. In the northern Great Lakes, immatures return in late May to early June, when adults are already well into their nesting season and must find unoccupied ranges.][ In Alaska, adults tend to migrate before immatures in early to mid-September, to the contrary of other areas, probably as heavy snowfall begins.][ Yearlings that were banded in southwestern ]Idaho
Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...
stayed for about 2 months after fledging, and then traveled long distances with a strong directional bias, with 9 of 12 recovered southeast of the study area- six of these moved south to coastal lowlands in Mexico] and as far as Guatemala, from their initial banding. In California, 35 hawks were banded as nestlings; 26 were recovered at less than 50 miles away, with multidirectional juvenile dispersals. Nestlings banded in Southern California sometimes actually traveled north as far as to Oregon, ranging to the opposite extreme as far as a banded bird from the Sierra Nevada (U.S.), Sierra Nevadas that moved south to Sinaloa
Sinaloa (), officially the Estado Libre y Soberano de Sinaloa ( en, Free and Sovereign State of Sinaloa), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. It is d ...
.[ Nestlings banded in ]Green County, Wisconsin
Green County is a county (United States), county located in the U.S. state of Wisconsin. As of the 2020 United States Census, 2020 census, the population was 37,093. Its county seat is Monroe, Wisconsin, Monroe. Green County is included in the M ...
, did not travel very far comparatively by October–November, but by December, recoveries were found in states including Illinois, Iowa, Texas, Louisiana, and Florida.
Diet
The red-tailed hawk is carnivorous
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 ...
, and a highly opportunistic feeder. Nearly any small animal they encounter may be viewed as potential food.[ Their most common prey are small mammals such as ]rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
s and lagomorph
The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (hares and rabbits) and the Ochotonidae (pikas). The name of the order is derived from the Ancient Greek ''lagos'' (λαγ ...
s, but they also consume birds, reptiles, fish, amphibian
Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...
s, and invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s. Prey varies considerably with regional and seasonal availability, but usually centers on rodents, accounting for up to 85% of a hawk's diet. In total, nearly 500 prey species have been recorded in their diet, almost as many as great horned owls have been recorded as taking.[Blumstein, D.T. (1986)]
''The Diets and Breeding Biology of Red-tailed Hawks in Boulder County: 1985 Nesting Season''
Colorado Division of Wildlife. When 27 North American studies are reviewed, mammals make up 65.3% of the diet by frequency, 20.9% by birds, 10.8% by reptiles, 2.8% by invertebrates, and 0.2% by amphibians and fish.[ The geometric mean body mass of prey taken by red-tailed hawks in North America is about based on a pair of compilation studies from across the continent, regionally varying at least from .] Staple prey (excluding invertebrates) has been claimed to weigh from , ranging roughly from the size of a small mouse
A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...
or 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 ...
to the size of a black-tailed jackrabbit
The black-tailed jackrabbit (''Lepus californicus''), also known as the American desert hare, is a common hare of the western United States and Mexico, where it is found at elevations from sea level up to . Reaching a length around , and a ...
(''Lepus californicus''). The daily food requirements range from 7 to 11.2% of their own body weight, so that about three 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 the equivalent weight are required daily for a typical range adult.[
The talons and feet of red-tailed hawks are relatively large for a ''Buteo'' hawk; in an average-sized adult red-tail, the "hallux-claw" or rear talon, the largest claw on all accipitrids, averages about .][ In fact, the talons of red-tails in some areas averaged of similar size to those of ferruginous hawks which can be considerably heavier and notably larger than those of the only slightly lighter Swainson's hawk.] This species may exert an average of about of pressure through its feet. Owing to its morphology, red-tailed hawks generally can attack larger prey than other ''Buteo'' hawks typically can, and are capable of selecting the largest prey of up to their own size available at the time of hunting, though in all likelihood numerically most prey probably weighs on average about 20% of the hawk's own weight (as is typical of many birds of prey).[Marti, C. D., Korpimäki, E., & Jaksić, F. M. (1993). ''Trophic structure of raptor communities: a three-continent comparison and synthesis''. In Current ornithology (pp. 47-137). Springer US.] Red-tailed hawks usually hunt by watching for prey activity from a high perch, also known as still hunting. Upon being spotted, prey is dropped down upon by the hawk. Red-tails often select the highest available perches within a given environment, since the greater the height they are at, the less flapping is required and the faster the downward glide they can attain toward nearby prey. If prey is closer than average, the hawk may glide at a steep downward angle with few flaps, if farther than average, it may flap a few swift wingbeats alternating with glides. Perch hunting is the most successful hunting method generally speaking for red-tailed hawks and can account for up to 83% of their daily activities (i.e. in winter).[ Wintering pairs may join together and aseasonally may join forces to group hunt agile prey that they may have trouble catching by themselves, such as ]tree squirrel
Tree squirrels are the members of the squirrel Family (biology), family (Sciuridae) commonly just referred to as "squirrels." They include more than 100 arboreal species native to all continents except Antarctica and Oceania.
They do not form a ...
s. This may consist of stalking opposites sides of a tree, to surround the squirrel and almost inevitably drive the rodent to be captured by one after being flushed by the other hawk.[
The most common flighted hunting method for red-tail is to cruise around over the ground with flap-and-glide type flight, interspersed occasionally with harrier-like quarters over the ground. This method is less successful than perch hunting, but seems relatively useful for capturing small birds and may show the best results while hunting in hilly country.][ Hunting red-tailed hawks readily use trees, bushes, or rocks for concealment before making a surprise attack, even showing a partial ability to dodge among trees in an ''Accipiter''-like fashion. Among thick stands of ]spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...
in Alaska, a dodging hunting flight was thought to be unusually important to red-tails living in extensive areas of conifers, with hawks even coming to the ground and walking hurriedly in prey pursuit especially if the prey was large, a similar behavior to goshawks.[ Additional surprisingly swift aerial hunting has reported in red-tails that habitually hunt bats in Texas. Here, the bat-hunting specialists stooped with half-closed wings, quite falcon-like, plowing through the huge stream of bats exiting their cave roosts, then zooming upwards with a bat in its talons. These hawks also flew parallel closely to the stream, then veer sharply into it and seize a bat.] In the neotropics
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...
, red-tails have shown the ability to dodge amongst forest canopy whilst hunting. In Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
, red-tailed hawks were recorded sailing to catch flying insects, a hunting method more typical of a Swainson's hawk. Alternately, they may drop to the ground to forage for insects like grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
s and beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
s as well as other invertebrates and probably amphibians and fish (except by water in the latter cases). Hunting afoot seems to be particularly prevalent among immatures. Young red-tailed hawks in northeastern Florida were recorded often extracting earthworm
An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...
s from near the surface of the ground and some had a crop full of earthworms after rains. Ground hunting is also quite common on Socorro Island
Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest ...
, where no native land mammals occur, and invertebrates are more significant to their overall diet.[ A red-tailed hawk was observed to incorporate an unconventional killing method, which was drowning a ]heron
The herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera ''Botaurus'' and ''Ixobrychus ...
immediately after capture. One red-tailed hawk was seen to try to grab a young ground squirrel and, upon missing it, screamed loudly, which in turn caused another young squirrel to break into a run, wherein it was captured. Whether this was an intentional hunting technique needs investigation.[ Upon capture, smaller prey is taken to a feeding perch, which is almost always lower than a hunting perch. Among small prey, rodents are often swallowed whole, as are ]shrew
Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different fa ...
s and small snakes, while birds are plucked and beheaded. Even prey as small as chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
s may take two or three bites to consume. Larger mammals of transportable size are at times beheaded and have part of their fur discarded, then leftovers are either stored in a tree or fall to the ground. Large prey, especially if too heavy to transport on the wing, is often dragged to a secluded spot and dismantled in various ways. If they can successfully carry what remains to a low perch, they tend to feed until full and then discard the rest.[
]
Mammals
Rodents are certainly the type of prey taken most often by frequency, but their contribution to prey biomass at nests can be regionally low, and the type, variety and importance of rodent prey can be highly variable. In total, well over 100 rodent species have turned up the diet of red-tailed hawks.[ Rodents of extremely varied sizes may be hunted by red-tails, with species ranging in size from the ]eastern harvest mouse
The eastern harvest mouse (''Reithrodontomys humulis'') is a species of rodent in the family Cricetidae.
It is endemic to the Southeastern United States.
Its natural habitats are subtropical or tropical seasonally wet or flooded lowland grassland ...
(''Reithrodontomys humulis'') to 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 (''Marmota ssp.''), weighing some in spring, although whether they can take full grown marmots is questionable. At least some attacks on adult marmots like groundhog
The groundhog (''Marmota monax''), also known as a woodchuck, is a rodent of the family Sciuridae, belonging to the group of large ground squirrels known as marmots.
The groundhog is a lowland creature of North America; it is found through mu ...
s (''Marmota monax'') are abortive. At times, the red-tailed hawk is thought of as a semi-specialized 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 ...
-catcher, but voles are a subsistence food that are more or less are taken until larger prey such as rabbits and squirrels can be captured. In an area of Michigan
Michigan () is a state in the Great Lakes region of the upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the 10th-largest state by population, the 11th-largest by area, and the ...
, immature hawks took almost entirely voles but adults were diversified feeders.[ Indeed, the ]meadow vole
The eastern meadow vole (''Microtus pennsylvanicus''), sometimes called the field mouse or meadow mouse, is a North American vole found in eastern Canada and the United States. Its range extends farther south along the Atlantic coast.
The weste ...
(''Microtus pennsylvanicus'') was the highest frequency prey species in 27 dietary studies across North America, accounting for up to 54% of the food at nests by frequency. It is quite rare for any one species to make up more than half of the food at any dietary study for red-tailed hawks.[ In total about 9 '']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 ...
'' species are known in the overall diet, with 5 other voles and lemming
A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings form the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which form part of the superfamily Muroidea, which also include ...
s known to be included in their prey spectrum.[ Another well-represented species was the ]prairie vole
The prairie vole (''Microtus ochrogaster'') is a small vole found in central North America. The vole has long, coarse grayish-brown fur on the upper portion of the body and yellowish fur on the lower portion of the body. It has short ears and a ...
(''Microtus ochrogaster''), which were the primary food, making up 26.4% of a sample of 1322, in eastern Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
. While crepuscular
In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of daylig ...
in primary feeding activity, voles are known to be active both day and night, and so are reliable food for hawks than most non-squirrel rodents, which generally are nocturnal in activity.[ Indeed, most other microtine rodents are largely inaccessible to red-tailed hawks due to their strongly nocturnal foraging patterns, even though 24 species outside of voles and lemmings are known to be hunted. ]Woodrat
A pack rat or packrat, also called a woodrat or trade rat, are any species in the North and Central American rodent genus ''Neotoma''. Pack rats have a rat-like appearance, with long tails, large ears, and large, black eyes. Pack rats are notice ...
s are taken as important supplemental prey in some regions, being considerably larger than most other crictetid rodents, and some numbers of North American deermouse (''Peromyscus maniculatus'') may turn up. The largest representation of the latter species was contributing 11.9% of the diet in the Great Basin
The Great Basin is the largest area of contiguous endorheic basin, endorheic watersheds, those with no outlets, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California ...
of Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
, making them the second best represented prey species there.[
] Considering this limited association with nocturnal rodents, the high importance of pocket gopher
Pocket gophers, commonly referred to simply as gophers, are burrowing rodents of the family Geomyidae. The roughly 41 speciesSearch results for "Geomyidae" on thASM Mammal Diversity Database are all endemic to North and Central America. They are ...
s in the diet of red-tailed hawks is puzzling to many biologists, as these tend to be highly nocturnal and elusive by day, rarely leaving the confines of their burrow. At least 8 species of pocket gopher are included in the prey spectrum (not to mention 5 species of pocket mice
Perognathinae is a subfamily of rodents consisting of two genera of pocket mice. Most species live in complex burrows within the deserts and grasslands of western North America, They feed mostly on seeds and other plant parts, which they carry i ...
). The northern pocket gopher (''Thomomys talpoides'') is particularly often reported and, by frequency, even turns up as the third most often recorded prey species in 27 American dietary studies. Presumably, hunting of pocket gophers by red-tails, which has possibly never been witnessed, occurs in dim light at first dawn and last light of dusk when they luck upon a gopher out foraging.[
By far, the most important prey among rodents are ]squirrel
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squ ...
s, as they are almost fully diurnal. All told, nearly 50 species from the squirrel family have turned up as food. In particular, where they are distributed, 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 are doubly attractive as a primary food source due to their ground dwelling habits, as red-tails prefer to attack prey that is terrestrial.[ There are also many disadvantages to ground squirrels as prey: they can escape quickly to the security of their burrows, they tend to be highly social and they are very effective and fast in response to alarm calls, and a good deal of species enter ]hibernation
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...
that in the coldest climates can range up to a 6 to 9-month period (although those in warmer climates with little to no snowy weather often have brief dormancy and no true hibernation). Nonetheless, red-tailed hawks are devoted predators of ground squirrels, especially catching incautious ones as they go out foraging (which more often than not are younger animals). A multi-year study conducted on San Joaquin Experimental Range
The San Joaquin Experimental Range is an ecosystem research experimental area in the foothills of the Sierra Nevada. The range is located in O'Neals, California, outside of the Sierra National Forest about north of Fresno, California. The range ...
in California, seemingly still the largest food study to date done for red-tailed hawks with 4031 items examined, showed that throughout the seasons the California ground squirrel
The California ground squirrel (''Otospermophilus beecheyi''), also known as the Beechey ground squirrel, is a common and easily observed ground squirrel of the western United States and the Baja California Peninsula; it is common in Oregon and ...
(''Otospermophilus beecheyi'') was the most significant prey, accounting for 60.8% of the breeding season diet and about 27.2% of the diet for hawks year-around. Because of the extremely high density of red-tailed hawks on this range, some pairs came to specialize on diverse alternate prey, which consisted variously of kangaroo rat
Kangaroo rats, small mostly nocturnal rodents of genus ''Dipodomys'', are native to arid areas of western North America. The common name derives from their bipedal form. They hop in a manner similar to the much larger kangaroo, but developed thi ...
s, 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, snakes or chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
s. One pair apparently lessened competition by focusing on pocket gopher
Pocket gophers, commonly referred to simply as gophers, are burrowing rodents of the family Geomyidae. The roughly 41 speciesSearch results for "Geomyidae" on thASM Mammal Diversity Database are all endemic to North and Central America. They are ...
s instead despite being near the center of ground squirrel activity.[
] In Snake River NCA, the primary food of red-tailed hawks was the Townsend's ground squirrel
Townsend's ground squirrel (''Urocitellus townsendii'') is a species of rodent in the family Sciuridae. It is found in high desert shrublands in several areas of the United States.
Distribution
Townsend's ground squirrel is found in the Great Ba ...
(''Urocitellus townsendii''), which made up nearly 21% of the food in 382 prey items across several years despite sharp spikes and crashes of the ground squirrel population there.[ The same species was the main food of red-tailed hawks in southeastern ]Washington
Washington commonly refers to:
* Washington (state), United States
* Washington, D.C., the capital of the United States
** A metonym for the federal government of the United States
** Washington metropolitan area, the metropolitan area centered on ...
, making up 31.2% of 170 items.[Fitzner, R. E., Rickard, W. H., Cadwell, L. L., & Rogers, L. E. (1981). ''Raptors of the Hanford site and nearby areas of southcentral Washington (No. PNL-3212)''. Battelle Pacific Northwest Labs., Richland, WA (USA).] An even closer predatory relationship was reported in the Centennial valley of Montana
Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...
and south-central Montana, where 45.4% of 194 prey items and 40.2% of 261 items, respectively, of the food of red-tails consisted of the Richardson's ground squirrel
Richardson's ground squirrel (''Urocitellus richardsonii''), also known as the dakrat or flickertail, is a North American ground squirrel in the genus ''Urocitellus''. Like a number of other ground squirrels, they are sometimes called prairie do ...
(''Urocitellus richardsonii'').[
] Locally in Rochester, Alberta
Rochester is a hamlet in northern Alberta, Canada within Athabasca County. It is east of Highway 2, north of Edmonton.
Demographics
In the 2021 Census of Population conducted by Statistics Canada, Rochester had a population of 72 living in ...
, Richardson's ground squirrel
Richardson's ground squirrel (''Urocitellus richardsonii''), also known as the dakrat or flickertail, is a North American ground squirrel in the genus ''Urocitellus''. Like a number of other ground squirrels, they are sometimes called prairie do ...
, estimated to average , were secondary in number to unidentified small rodents but red-tails in the region killed an estimated 22–60% of the area’s ground squirrel, a large dent in the squirrel’s population.[
] Further east, ground squirrels are not so reliably distributed, but one study in southern Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...
, in one of several quite different dietary studies in that state, the thirteen-lined ground squirrel
The thirteen-lined ground squirrel (''Ictidomys tridecemlineatus''), also known as the striped gopher, leopard ground squirrel, squinney, (formerly known as the leopard-spermophile in the age of Audubon), is a ground squirrel that is widely distr ...
(''Ictidomys tridecemlineatus'') was the main prey species, making up 29.7% of the diet (from a sample of 165).[
][
]
In Kluane Lake
Kluane Lake is located in the southwest area of the Yukon. It is the largest lake contained entirely within Yukon at approximately , and long.
Kluane Lake is located approximately northwest of Haines Junction. The Alaska Highway follows most of ...
, Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
, Arctic ground squirrel
The Arctic ground squirrel (''Urocitellus parryii'') (Inuktitut: ''ᓯᒃᓯᒃ, siksik'') is a species of ground squirrel native to the Arctic and Subarctic of North America and Asia. People in Alaska, particularly around the Aleutians, refer to ...
s (''Spermophilus parryii'') were the main overall food for Harlan’s red-tailed hawks, making up 30.8% of a sample of 1074 prey items. When these ground squirrels enter their long hibernation, the breeding Harlan’s hawks migrate south for the winter.[Doyle, F. I. (2001)]
''Timing of reproduction by red-tailed hawks, northern goshawks and great horned owls in the Kluane Boreal Forest of Southwestern Yukon''
PhD Thesis. University of British Columbia. Nearly as important in Kluane Lake was the American red squirrel
The American red squirrel (''Tamiasciurus hudsonicus'') is one of three species of tree squirrels currently classified in the genus ''Tamiasciurus'', known as the pine squirrels (the others are the Douglas squirrel, ''T. douglasii'', and the sou ...
(''Tamiasciurus hudsonicus''), which constituted 29.8% of the above sample. Red squirrels are highly agile dwellers on dense spruce stands, which has caused biologists to ponder how the red-tailed hawks are able to routinely catch them. It is possible that the hawks catch them on the ground such as when squirrels are digging their caches, but theoretically the dark color of the Harlan’s hawks may allow them to more effectively ambush the squirrels within the forests locally.[ While American red squirrel turn up not infrequently as supplementary prey elsewhere in North America, other ]tree squirrel
Tree squirrels are the members of the squirrel Family (biology), family (Sciuridae) commonly just referred to as "squirrels." They include more than 100 arboreal species native to all continents except Antarctica and Oceania.
They do not form a ...
s seem to be comparatively infrequently caught, at least during the summer breeding season. It is known that pairs of red-tailed hawks will cooperative hunt tree squirrels at times, probably mostly between late fall and early spring. Fox squirrel
The fox squirrel (''Sciurus niger''), also known as the eastern fox squirrel or Bryant's fox squirrel, is the largest species of tree squirrel native to North America. Despite the differences in size and coloration, it is sometimes mistaken for ...
s (''Sciurus niger''), the largest of North America’s tree squirrels at , are fairly regular supplemental prey but the lighter, presumably more agile eastern gray squirrel
The eastern gray squirrel (''Sciurus carolinensis''), also known, particularly outside of North America, as simply the grey squirrel, is a tree squirrel in the genus ''Sciurus''. It is native to eastern North America, where it is the most prodi ...
(''Sciurus carolinensis'') appears to be seldom caught based on dietary studies. While adult marmot may be difficult for red-tailed hawks to catch, young marmots are readily taken in numbers after weaning, such as a high frequency of yellow-bellied marmot
The yellow-bellied marmot (''Marmota flaviventris''), also known as the rock chuck, is a large, stout-bodied ground squirrel in the marmot genus. It is one of fourteen species of marmots, and is native to mountainous regions of southwestern Canad ...
(''Marmota flaviventris'') in Boulder, Colorado
Boulder is a home rule city that is the county seat and most populous municipality of Boulder County, Colorado, United States. The city population was 108,250 at the 2020 United States census, making it the 12th most populous city in Color ...
. Another grouping of squirrel
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squ ...
s but at the opposite end of the size spectrum for squirrels, the chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
s are also mostly supplemental prey but are considered more easily caught than tree squirrels, considering that they are more habitual terrestrial foragers.[ In central ]Ohio
Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...
, eastern chipmunk
The eastern chipmunk (''Tamias striatus'') is a chipmunk species found in eastern North America. It is the only living member of the chipmunk genus ''Tamias''.
Etymology
The name "chipmunk" comes from the Ojibwe word ''ajidamoo'' (or possibl ...
s (''Tamias striatus''), the largest species of chipmunk at an average weight of , were actually the leading prey by number, making up 12.3% of a sample of 179 items.[
Outside of rodents, the most important prey for North American red-tailed hawks is rabbits and hares, of which at least 13 species are included in their prey spectrum. By biomass and reproductive success within populations, these are certain to be their most significant food source (at least in North America).][ Adult '']Sylvilagus
Cottontail rabbits are the leporid species in the genus ''Sylvilagus'', found in the Americas. Most ''Sylvilagus'' species have stub tails with white undersides that show when they retreat, giving them their characteristic name. However, this ...
'' rabbits known to be hunted by red-tails can range from the brush rabbit
The brush rabbit (''Sylvilagus bachmani''), or western brush rabbit, or Californian brush rabbit, is a species of cottontail rabbit found in western coastal regions of North America, from the Columbia River in Oregon to the southern tip of the ...
(''Sylvilagus bachmani'') to the Tres Marias rabbit
The Tres Marias cottontail or Tres Marias rabbit (''Sylvilagus graysoni'') is a species of mammal in the family Leporidae. Distribution and habitat
It is endemic to the Tres Marias Islands, part of the Mexican state of Nayarit. The rabbit is ...
(''Sylvilagus graysoni'') at while all leporids hunted may range the pygmy rabbit
The pygmy rabbit (''Brachylagus idahoensis'') is a rabbit species native to the United States. It is also the only native rabbit species in North America to dig its own burrow. The pygmy rabbit differs significantly from species within either the ...
(''Brachylagus idahoensis'') to hares and jackrabbits potentially up twice the hawk’s own weight. While primarily crepuscular
In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of daylig ...
in peak activity, rabbits and hares often foraging both during day and night and so face almost constant predatory pressure from a diverse range of predators. Male red-tailed hawks or pairs which are talented rabbit hunters are likely have higher than average productivity due to the size and nutrition of the meal ensuring healthy, fast-growing offspring.[ Most widely reported are the ]cottontail
Cottontail rabbits are the leporid species in the genus ''Sylvilagus'', found in the Americas. Most ''Sylvilagus'' species have stub tails with white undersides that show when they retreat, giving them their characteristic name. However, this ...
s, which the three most common North America varieties softly grading into mostly allopatric ranges, being largely segregated by habitat preferences where they overlap in distribution. Namely, in descending order of reportage were: the eastern cottontail
The eastern cottontail (''Sylvilagus floridanus'') is a New World cottontail rabbit, a member of the family Leporidae. It is the most common rabbit species in North America.
Distribution
The eastern cottontail can be found in meadows and shrubby ...
(''Sylvilagus floridanus''), the second most widely reported prey species overall in North America and with maximum percentage known in a given study was 26.4% in Oklahoma
Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...
(out of 958 prey items), the mountain cottontail
The mountain cottontail or Nuttall's cottontail (''Sylvilagus nuttallii'') is a species of mammal in the family Leporidae. It is found in Canada and the United States.
Description
The mountain cottontail is a small rabbit but its size is rel ...
(''Sylvilagus nuttallii''), maximum representation being 17.6% out of a sample of 478 in Kaibab Plateau
The Kaibab Plateau is a plateau almost entirely in Coconino County, Arizona (but extending slightly north into Kane County, Utah) in the Southwestern United States. The high plain is also known as the Buckskin Mountain, Buckskin Plateau, and K ...
, Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
and the desert cottontail
The desert cottontail (''Sylvilagus audubonii''), also known as Audubon's cottontail, is a New World cottontail rabbit, and a member of the family Leporidae. Unlike the European rabbit (''Oryctolagus cuniculus''), they do not form social burrow s ...
(''Sylvilagus audubonii''), maximum representation being 22.4% out of a sample of 326 in west-central Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
. Black-tailed jackrabbit
The black-tailed jackrabbit (''Lepus californicus''), also known as the American desert hare, is a common hare of the western United States and Mexico, where it is found at elevations from sea level up to . Reaching a length around , and a ...
s (''Lepus californicus'') are even more intensely focused upon as a food source by the hawks found in the west, particularly the Great Basin
The Great Basin is the largest area of contiguous endorheic basin, endorheic watersheds, those with no outlets, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California ...
. This species is likely the largest prey routinely hunted by red-tails, and the mean prey size where jackrabbits are primarily hunted is the highest known overall. When jackrabbit numbers crash, red-tailed hawk productivity tends to decline as well. In northern Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
, black-tailed jackrabbits made up 55.3% by number of a sample of 329. Elsewhere, they are usually somewhat secondary by number. Mean sizes of jackrabbits taken can range up to approximately , but probably quantitatively mostly juvenile and yearling jackrabbits are caught. Prime adult jackrabbits, with weights at times exceeding , are difficult and taken infrequently, short of by particularly large and aggressive female red-tails.[ Other even larger species are sometimes taken as prey such as the ]white-tailed jackrabbit
The white-tailed jackrabbit (''Lepus townsendii''), also known as the prairie hare and the white jack, is a species of hare found in western North America. Like all hares and rabbits, it is a member of the family Leporidae of order Lagomorpha ...
(''Lepus townsendii''), but whether this includes healthy adults, as they average over , is unclear.[
In the ]boreal forests
Taiga (; rus, тайга́, p=tɐjˈɡa; relates to Mongolic and Turkic languages), generally referred to in North America as a boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces ...
of Canada and Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
, red-tails are fairly dependent on the snowshoe hare
The snowshoe hare (''Lepus americanus''), also called the varying hare or snowshoe rabbit, is a species of hare found in North America. It has the name "snowshoe" because of the large size of its hind feet. The animal's feet prevent it from sink ...
(''Lepus americanus''), falling somewhere behind the great horned owl
The great horned owl (''Bubo virginianus''), also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air"), or the hoot owl, is a large owl native to the Americas. It is an extrem ...
and ahead of the northern goshawk
The northern goshawk (; ''Accipiter gentilis'') is a species of medium-large bird of prey, raptor in the Family (biology), family Accipitridae, a family which also includes other extant diurnal raptors, such as eagles, buzzards and harrier (bird) ...
in their regional reliance on this food source.[ The hunting preferences of red-tails who rely on snowshoe hares is variable. In ]Rochester, Alberta
Rochester is a hamlet in northern Alberta, Canada within Athabasca County. It is east of Highway 2, north of Edmonton.
Demographics
In the 2021 Census of Population conducted by Statistics Canada, Rochester had a population of 72 living in ...
, 52% of snowshoe hares caught were adults, such prey estimated to average , and adults, in some years, were six times more often taken than juvenile hares, which averaged an estimated . 1.9–7.1% of adults in the regional population of Rochester were taken by red-tails, while only 0.3–0.8 of juvenile hares were taken by them. Despite their reliance on it, only 4% (against 53.4% of the biomass) of the food by frequency here was made up of hares.[ On the other hand, in Kluane Lake, ]Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
, juvenile hares were taken roughly 11 times more often than adults, despite the larger size of adults here, averaging , and that the overall prey base was less diverse at this more northerly clime. In both Rochester and Kluane Lake, the number of snowshoe hares taken was considerably lower than numbers of ground squirrels taken. The differences of average characteristics of snowshoe hares that were hunted may be partially due to habitat (extent of bog
A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and muskeg; a ...
openings to dense forest) or topography.[ Another member of the ]Lagomorpha
The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (hares and rabbits) and the Ochotonidae (pikas). The name of the order is derived from the Ancient Greek ''lagos'' (λαγ ...
order has been found in the diet, the much smaller American pika
The American pika (''Ochotona princeps''), a diurnality, diurnal species of pika, is found in the mountains of western North America, usually in boulder fields at or above the tree line. They are herbivorous, smaller relatives of rabbits and ha ...
(''Ochotona princeps''), at , but is not known to be common prey.
A diversity of mammals may be consumed opportunistically outside of the main food groups of rodents and leporids, but usually occur in low numbers. At least five species each are taken of shrew
Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different fa ...
s and mole
Mole (or Molé) may refer to:
Animals
* Mole (animal) or "true mole", mammals in the family Talpidae, found in Eurasia and North America
* Golden moles, southern African mammals in the family Chrysochloridae, similar to but unrelated to Talpida ...
s, ranging in size from their smallest mammalian prey, the cinereus (''Sorex cinereus'') and least shrew
The North American least shrew (''Cryptotis parvus'') is one of the smallest mammals, growing to be only up to 3 inches long. It has a long pointed snout and a tail never more than twice the length of its hind foot. The dense fur coat is e ...
s (''Cryptotis parva''), which both weigh about , to Townsend's mole
The Townsend's mole (''Scapanus townsendii'') is a fossorial mammal in the family Talpidae, and is the largest North American mole. It was named after the American naturalist John Kirk Townsend. The name was selected at the request of Thomas Nut ...
(''Scapanus townsendii''), which weighs about . A respectable number of the eastern mole
The Eastern Mole or Common Mole (''Scalopus aquaticus'') is a medium-sized North American mole. It is the only member of genus ''Scalopus''. It is found in forested and open areas with moist sandy soils in northern Mexico, the eastern United ...
(''Scalopus aquaticus'') were recorded in studies from Oklahoma
Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...
and Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
.[ Four species of bat have been recorded in their foods.][ The red-tailed hawks local to the large cave colonies of ]Mexican free-tailed bat
The Mexican free-tailed bat or Brazilian free-tailed bat (''Tadarida brasiliensis'') is a medium-sized bat native to the Americas, so named because its tail can be almost half its total length and is not attached to its uropatagium. It has been ...
s (''Tadarida brasiliensis'') in Texas can show surprising agility, some of the same hawks spending their early evening and early morning hours in flight patrolling the cave entrances in order to stoop suddenly on these flighted mammals.[ Larger miscellaneous mammalian prey are either usually taken as juveniles, like the ]nine-banded armadillo
The nine-banded armadillo (''Dasypus novemcinctus''), also known as the nine-banded long-nosed armadillo or common long-nosed armadillo, is a mammal found in North, Central, and South America, making it the most widespread of the armadillos. It ...
(''Dasypus novemcinctus''), or largely as 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 ...
, like the Virginia opossum
The Virginia opossum (''Didelphis virginiana''), also known as the North American opossum, is the only opossum living north of Mexico, its range extending south into Central America. It is the northernmost marsupial in the world. In the United S ...
(''Didelphis virginiana'').[ Small ]carnivora
Carnivora is a Clade, monophyletic order of Placentalia, placental mammals consisting of the most recent common ancestor of all felidae, cat-like and canidae, dog-like animals, and all descendants of that ancestor. Members of this group are f ...
ns may be taken, usually consisting of much smaller mustelid
The Mustelidae (; from Latin ''mustela'', weasel) are a family of carnivorous mammals, including weasels, badgers, otters, ferrets, martens, minks and wolverines, among others. Mustelids () are a diverse group and form the largest family in ...
s, like the long-tailed weasel
The long-tailed weasel (''Neogale frenata''), also known as the bridled weasel, masked ermine, or big stoat, is a species of Mustelidae, mustelid distributed from southern Canada throughout all the United States and Mexico, southward through all ...
(''Neogale frenata''), which was surprisingly widely taken as a supplemental prey species.[ Adult ]ringtail
The ringtail (''Bassariscus astutus'') is a mammal of the raccoon family native to arid regions of North America. It is widely distributed and well adapted to disturbed areas. It has been legally trapped for its fur. It is listed as Least Co ...
s (''Bassariscus astutus''), which are about the same weight as a red-tailed hawk at , are taken as prey occasionally.[ Larger ]carnivora
Carnivora is a Clade, monophyletic order of Placentalia, placental mammals consisting of the most recent common ancestor of all felidae, cat-like and canidae, dog-like animals, and all descendants of that ancestor. Members of this group are f ...
n remains are sometimes found amongst their foods, but most are likely taken as juveniles or smaller range adults, or otherwise consumed only as carrion. Some of the relatively larger carnivorans red-tailed hawks have been known to eat have included 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''), kit fox
The kit fox (''Vulpes macrotis'') is a fox species that inhabits arid and semi-arid regions of the southwestern United States and northern and central Mexico. These foxes are the smallest of the four species of ''Vulpes'' occurring in North Amer ...
(''Vulpes macrotis''), white-nosed coati
The white-nosed coati (''Nasua narica''), also known as the coatimundi (), is a species of coati and a member of the family Procyonidae (raccoons and their relatives). Local Spanish names for the species include ''pizote'', ''antoon'', and ''te ...
(''Nasua narica''), raccoon
The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...
(''Procyon lotor''), striped skunk
The striped skunk (''Mephitis mephitis'') is a skunk of the genus '' Mephitis'' that occurs across much of North America, including southern Canada, the United States, and northern Mexico. It is currently listed as least concern by the IUCN on ac ...
(''Mephitis mephitis'') and domestic cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members o ...
s (''Felis catus'').[Bildstein, K. L. (1987). Behavioral ecology of red-tailed hawks (''Buteo jamaicensis''), rough-legged hawks (''Buteo lagopus''), northern harriers (''Circus cyaneus''), and American kestrels (''Falco sparverius'') in south central Ohio'' (No. 04; USDA, QL696. F3 B5.).] A red-tailed hawk was filmed killing a small cat in a city area. Many of these medium-sized carnivorans are probably visited as roadkill, especially during the sparser winter months, but carrion has turned up more widely than previously thought. Some nests have been found (to the occasional "shock" of researchers) with body parts from large domestic stock like sheep
Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...
(''Ovis aries''), pig
The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus '' Sus'', is an omnivorous, domesticated, even-toed, hoofed mammal. It is variously considered a subspecies of ''Sus s ...
s (''Sus domesticus''), horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...
s (''Equus caballus '') 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 ...
(''Bos taurus'') (not to mention wild varieties like deer
Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...
), which red-tails must visit when freshly dead out on pastures and take a couple talonfuls of meat.[ In one instance, a red-tailed hawk was observed to kill a small but seemingly healthy ]lamb
Lamb or The Lamb may refer to:
* A young sheep
* Lamb and mutton, the meat of sheep
Arts and media Film, television, and theatre
* ''The Lamb'' (1915 film), a silent film starring Douglas Fairbanks Sr. in his screen debut
* ''The Lamb'' (1918 ...
. These are born heavier than most red-tails at but in this case, the hawk was scared away before it could consume its kill by the rifle fire of the shepherd who witnessed the instance.
Birds
Like most (but not all) ''Buteo
''Buteo'' is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in the New World (Etymology: ''Buteo'' is the Latin name o ...
'' hawks, red-tailed hawks do not primarily hunt birds in most areas, but can take them fairly often whenever they opportune upon some that are vulnerable. Birds are, by far, the most diverse class in the red-tailed hawk’s prey spectrum, with well over 200 species known in their foods.[ In most circumstances where birds become the main food of red-tailed hawks, it is in response to ample local populations of ]galliforms
Galliformes is an order (biology), order of heavy-bodied ground-feeding birds that includes turkey (bird), turkeys, chickens, Old World quail, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems ...
. As these are meaty, mostly terrestrial birds which usually run rather than fly from danger (although all wild species in North America are capable of flight), galliforms are ideal avian prey for red-tails. Some 23 species of galliforms are known to be taken by red-tailed hawks, about a third of these being species introduced by humans.[ Native quails of all five North American species may expect occasional losses.][ All 12 species of ]grouse
Grouse are a group of birds from the order Galliformes, in the family Phasianidae. Grouse are presently assigned to the tribe Tetraonini (formerly the subfamily Tetraoninae and the family Tetraonidae), a classification supported by mitochondr ...
native to North America are also occasionally included in their prey spectrum. In the state of Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...
, two large studies, from Waupun
Waupun is a city in Dodge County, Wisconsin, Dodge and Fond du Lac County, Wisconsin, Fond du Lac counties in the U.S. state of Wisconsin. The population was 11,344 at the 2020 census. Of this, 7,795 were in Dodge County, and 3,549 were in Fond du ...
and Green County, found the main prey species to be the ring-necked pheasant
The common pheasant (''Phasianus colchicus'') is a bird in the pheasant family (Phasianidae). The genus name comes from Latin ''phasianus'', "pheasant". The species name ''colchicus'' is Latin for "of Colchis" (modern day Georgia), a country on ...
(''Phasianus colchicus''), making up 22.7% of a sample of 176 and 33.8% of a sample of 139, respectively. With a body mass averaging , adult pheasants are among the largest meals that male red-tails are likely to deliver short of adult rabbits and hares and therefore these nests tend to be relatively productive. Despite being not native to North America, pheasants usually live in a wild state. Chickens (''Gallus gallus domesticus'') are also taken throughout North America, with all Wisconsin studies also found large numbers of them, making up as much as 14.4% of the diet. Many studies reflect that free-ranging chickens are vulnerable to red-tailed hawks although somewhat lesser numbers are taken by them overall in comparison to nocturnal predators (i.e. 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 ...
s and foxes
Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush'').
Twelve sp ...
) and goshawk
Goshawk may refer to several species of birds of prey, mainly in the genus ''Accipiter'':
* Northern goshawk, ''Accipiter gentilis'', often referred to simply as the goshawk, since it is the only goshawk found in much of its range (in Europe and N ...
s.[ In ]Rochester, Alberta
Rochester is a hamlet in northern Alberta, Canada within Athabasca County. It is east of Highway 2, north of Edmonton.
Demographics
In the 2021 Census of Population conducted by Statistics Canada, Rochester had a population of 72 living in ...
, fairly large numbers of ruffed grouse
The ruffed grouse (''Bonasa umbellus'') is a medium-sized grouse occurring in forests from the Appalachian Mountains across Canada to Alaska. It is the most widely distributed game bird in North America. It is non-migratory. It is the only specie ...
(''Bonasa umbellus'') were taken but relatively more juveniles were taken of this species than the two other main contributors to biomass here, snowshoe hare and Townsend’s ground squirrel, as they are fairly independent early on and more readily available. Here the adult grouse was estimated to average against the average juvenile which in mid-summer averaged .[
Beyond galliforms, three other quite different families of birds make the most significant contributions to the red-tailed hawk’s avian diet. None of these three families are known as particularly skilled or swift fliers, but are generally small enough that they would generally easily be more nimble in flight. One of these are the ]woodpecker
Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks, and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar, and the extreme polar regions. ...
s, if only for one species, the northern flicker
The northern flicker or common flicker (''Colaptes auratus'') is a medium-sized bird of the woodpecker family. It is native to most of North America, parts of Central America, Cuba, and the Cayman Islands, and is one of the few woodpecker spec ...
(''Colaptes auratus''), which was the best represented bird species in the diet in 27 North American studies and was even the fourth most often detected prey species of all.[ Woodpeckers are often a favorite in the diet of large raptors as their relatively slow, undulating flight makes these relatively easy targets. The flicker in particular is a highly numerous species that has similar habitat preferences to red-tailed hawks, preferring fragmented landscapes with trees and openings or parkland-type wooded mosaics, and often forage on the ground for ants, which may make them even more susceptible. Varied other woodpecker species may turn up in their foods, from the smallest to the largest extant in North America, but are much more infrequently detected in dietary studies.][ Another family relatively often selected prey family are ]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, which despite their relatively large size, formidable mobbing abilities and intelligence are also slower than average fliers for passerines. 14 species of corvid are known to fall prey to red-tailed hawks.[ In the ]Kaibab Plateau
The Kaibab Plateau is a plateau almost entirely in Coconino County, Arizona (but extending slightly north into Kane County, Utah) in the Southwestern United States. The high plain is also known as the Buckskin Mountain, Buckskin Plateau, and K ...
, the Steller's jay
Steller's jay (''Cyanocitta stelleri'') is a bird native to western North America and the mountains of Central America, closely related to the blue jay found in eastern North America. It is also known as the long-crested jay, mountain jay, and pin ...
(''Cyanocitta stelleri'') were the fourth most identified prey species (10.3% of the diet).[ ]American crow
The American crow (''Corvus brachyrhynchos'') is a large passerine bird species of the family Corvidae. It is a common bird found throughout much of North America. American crows are the New World counterpart to the carrion crow of Europe and th ...
s are also regularly detected supplemental prey in several areas.[ Even the huge ]common raven
The common raven (''Corvus corax'') is a large all-black passerine bird. It is the most widely distributed of all corvids, found across the Northern Hemisphere. It is a raven known by many names at the subspecies level; there are at least e ...
(''Corvus corax''), at at least as large as red-tailed hawk itself, may fall prey to red-tails, albeit very infrequently and only in a well-staged ambush.[ One of the most surprising heavy contributors are the ]icterid
Icterids () or New World blackbirds make up a family, the Icteridae (), of small to medium-sized, often colorful, New World passerine birds. Most species have black as a predominant plumage color, often enlivened by yellow, orange, or red. The ...
s, despite their slightly smaller size and tendency to travel in large, wary flocks, 12 species are known to be hunted.[ One species pair, the ]meadowlark
Meadowlarks are New World grassland birds belonging to genera ''Sturnella'' and ''Leistes''.
This group includes seven species of largely insectivorous grassland birds. In all species the male at least has a black or brown back and extensively ...
s, are most often selected as they do not flock in the same ways as many other icterids and often come to the ground, throughout their life history, rarely leaving about shrub-height. The western meadowlark
The western meadowlark (''Sturnella neglecta'') is a medium-sized icterid bird, about in length. It nests on the ground in open grasslands across western and central North America. It feeds mostly on bugs, but will also feed on seeds and berri ...
(''Sturnella neglecta''), in particular, was the third most often detected bird prey species in North America.[ ]Red-winged blackbird
The red-winged blackbird (''Agelaius phoeniceus'') is a passerine bird of the family Icteridae found in most of North America and much of Central America. It breeds from Alaska and Newfoundland south to Florida, the Gulf of Mexico, Mexico, and ...
s (''Agelaius phoeniceus'') which are probably too small, at an average weight of , and fast for a red-tailed hawk to ever chase on the wing (and do travel in huge flocks, especially in winter) are nonetheless also quite often found in their diet, representing up to 8% of the local diet for red-tails. It is possible that males, which are generally bold and often select lofty perches from which to display, are most regularly ambushed.[ One bird species that often flocks with red-winged blackbirds in winter is even better represented in the red-tail’s diet, the non-native ]European starling
The common starling or European starling (''Sturnus vulgaris''), also known simply as the starling in Great Britain and Ireland, is a medium-sized passerine bird in the starling family, Sturnidae. It is about long and has glossy black plumage ...
(''Sturnus vulgaris''), being the second most numerous avian prey species and seventh overall in North America.[ Although perhaps most vulnerable when caught unaware while calling atonally on a perch, a few starlings (or various blackbirds) may be caught by red-tails which test the agile, twisting murmurations of birds by flying conspicuously towards the flock, to intentionally disturb them and possibly detect lagging, injured individual birds that can be caught unlike healthy birds. However, this behavior has been implied rather than verified.][
Over 50 passerine species from various other families beyond corvids, icterids and starlings are included in the red-tailed hawks' prey spectrum but are caught so infrequently as to generally not warrant individual mention.][ Non-passerine prey taken infrequently may include but are not limited to ]pigeon
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
s and dove
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
s, cuckoo
Cuckoos are birds in the Cuculidae family, the sole taxon in the order Cuculiformes . The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals and anis. The coucals and anis are sometimes separ ...
s, nightjar
Nightjars are medium-sized nocturnal or crepuscular birds in the family Caprimulgidae and order Caprimulgiformes, characterised by long wings, short legs, and very short bills. They are sometimes called goatsuckers, due to the ancient folk ta ...
s, kingfishers
Kingfishers are a family, the Alcedinidae, of small to medium-sized, brightly colored birds in the order Coraciiformes. They have a cosmopolitan distribution, with most species found in the tropical regions of Africa, Asia, and Oceania, ...
and parrots.[ However, of some interest, is the extreme size range of birds that may be preyed upon. Red-tailed hawks in Caribbean islands seem to catch small birds more frequently due to the paucity of vertebrate prey diversity here. Birds as small as the ]elfin woods warbler
The elfin woods warbler (''Setophaga angelae'') is a species of bird endemic to Puerto Rico, where it is local and uncommon. Discovered in 1968 and described in 1972, it is the most recently described New World warbler (family Parulidae).
The ...
(''Setophaga angelae'') and the bananaquit
The bananaquit (''Coereba flaveola'') is a species of passerine bird in the tanager family Thraupidae. Before the development of molecular genetics in the 21st century, its relationship to other species was uncertain and it was either placed with ...
(''Coereba flaveola'') may turn up not infrequently as food. How red-tails can catch prey this small and nimble is unclear (perhaps mostly the even smaller nestlings or fledglings are depredated).[ In California, most avian prey was stated to be between the size of a ]starling
Starlings are small to medium-sized passerine birds in the family Sturnidae. The Sturnidae are named for the genus ''Sturnus'', which in turn comes from the Latin word for starling, ''sturnus''. Many Asian species, particularly the larger ones, ...
and a quail
Quail is a collective name for several genera of mid-sized birds generally placed in the order Galliformes. The collective noun for a group of quail is a flock, covey, or bevy.
Old World quail are placed in the family Phasianidae, and New Wor ...
.[ Numerous ]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 may be preyed upon including at least 22 species of shorebirds
245px, A flock of Dunlins and Red knots">Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots
Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflat ...
, at least 17 species of 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 ...
, at least 8 species of heron
The herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera ''Botaurus'' and ''Ixobrychus ...
and egret
Egrets ( ) are herons, generally long-legged wading birds, that have white or buff plumage, developing fine plumes (usually milky white) during the breeding season. Egrets are not a biologically distinct group from herons and have the same build ...
s and at least 8 species of rails
Rail or rails may refer to:
Rail transport
*Rail transport and related matters
*Rail (rail transport) or railway lines, the running surface of a railway
Arts and media Film
* ''Rails'' (film), a 1929 Italian film by Mario Camerini
* ''Rail'' ( ...
, plus a smaller diversity of grebe
Grebes () are aquatic diving birds in the order Podicipediformes . Grebes are widely distributed freshwater birds, with some species also found in marine habitats during migration and winter. Some flightless species exist as well, most notably ...
s, shearwaters
Shearwaters are medium-sized long-winged seabirds in the petrel family Procellariidae. They have a global marine distribution, but are most common in temperate and cold waters, and are pelagic outside the breeding season.
Description
These tub ...
and ibises
The ibises () (collective plural ibis; classical plurals ibides and ibes) are a group of long-legged wading birds in the family Threskiornithidae, that inhabit wetlands, forests and plains. "Ibis" derives from the Latin and Ancient Greek wo ...
.[ These may range to as small as the tiny, mysterious and "mouse-like" black rail (''Laterallus jamaicensis''), weighing an average of , and ]snowy plover
The snowy plover (''Charadrius nivosus'') is a small wader in the plover bird family, typically about 5-7" in length. It breeds in the southern and western United States, the Caribbean, Ecuador, Peru, and Chile. Long considered to be a subspecie ...
(''Charadrius nivosus''), weighing an average of (how they catch adults of this prey is not known), to some gull
Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, m ...
s, duck
Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form t ...
s and geese
A goose (plural, : geese) is a bird of any of several waterfowl species in the family (biology), family Anatidae. This group comprises the genera ''Anser (bird), Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some o ...
as heavy or heavier than a red-tailed hawk itself.
How large of a duck that red-tailed hawks can capture may be variable. In one instance, a red-tailed hawk failed to kill a healthy drake red-breasted merganser
The red-breasted merganser (''Mergus serrator'') is a diving duck, one of the sawbills. The genus name is a Latin word used by Pliny and other Roman authors to refer to an unspecified waterbird, and ''serrator'' is a sawyer from Latin ''serra'', ...
(''Mergus serrator''), with this duck estimated to weigh , later the same red-tail was able to dispatch a malnourished red-necked grebe
The red-necked grebe (''Podiceps grisegena'') is a migratory aquatic bird found in the temperate regions of the northern hemisphere. Its wintering habitat is largely restricted to calm waters just beyond the waves around ocean coasts, although ...
(''Podiceps grisegena'') (a species usually about as heavy as the merganser), weighing an estimated . However, in interior Alaska, locally red-tailed hawks have become habitual predators of adult ducks, ranging from green-winged teal
The green-winged teal (''Anas carolinensis'') is a common and widespread duck that breeds in the northern areas of North America except on the Aleutian Islands. It was considered Conspecificity, conspecific with the Eurasian teal (''A. crecca'') ...
(''Anas carolinensis'') to mallard
The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa, and has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Arge ...
(''Anas platyrhynchos'').[ Even larger, occasionally adult ]Ross's goose
The Ross's goose (''Anser rossii'') is a white goose with black wingtips and a relatively short neck. It is the smallest of the three " white geese" that breed in North America. It is similar in appearance to a white-phase snow goose, but about 4 ...
(''Chen rossii''), weighing on average , have been killed as well. Also, a non-native Egyptian goose
The Egyptian goose (''Alopochen aegyptiaca'') is a member of the duck, goose, and swan family Anatidae. It is native to Africa south of the Sahara and the Nile Valley.
Egyptian geese were considered sacred by the Ancient Egyptians, and appeared ...
(''Alopochen aegyptiaca''), in which adults average , was killed by a red-tail in Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
. There are several known instances of predation on adult greater sage grouse
The greater sage-grouse (''Centrocercus urophasianus''), also known as the sagehen, is the largest grouse (a type of bird) in North America. Its range is sagebrush country in the western United States and southern Alberta and Saskatchewan, Canad ...
(''Centrocercus urophasianus''), although mainly females are reported taken, these averaging depending on region. Some adult male sage grouse may have been attacked but, as these average from , this needs verification.[ Even larger, in at least once case a grown hatch-year bird was caught of the rare, non-native ]Himalayan snowcock
The Himalayan snowcock (''Tetraogallus himalayensis'') is a snowcock in the pheasant family Phasianidae found across the Himalayan ranges and parts of the adjoining Pamir range of Asia. It is found on alpine pastures and on steep rocky cliffs wh ...
(''Tetraogallus himalayensis''), this species averaging in adults. Red-tailed hawks are a threat to the poults typically of the wild turkey
The wild turkey (''Meleagris gallopavo'') is an Upland game bird, upland ground bird native to North America, one of two extant species of Turkey (bird), turkey and the heaviest member of the order Galliformes. It is the ancestor to the domestic ...
(''Meleagris gallopavo''). However, in one instance, an immature red-tail was observed trying to attack an adult female turkey, which would weigh about (on average). However this red-tail was unable to overpower the turkey hen. Additionally, young domestic turkeys, weighing up to at least or more, have been killed by red-tailed hawks. Other than wild turkeys, other larger birds occasionally lose young to red-tails such as trumpeter swan
The trumpeter swan (''Cygnus buccinator'') is a species of swan found in North America. The heaviest living bird native to North America, it is also the largest extant species of waterfowl, with a wingspan of 185 to 250 cm (6 ft 2 in to 8 ft 2 ...
s (''Cygnus buccinator''), sandhill crane
The sandhill crane (''Antigone canadensis'') is a species of large crane of North America and extreme northeastern Siberia. The common name of this bird refers to habitat like that at the Platte River, on the edge of Nebraska's Sandhills on t ...
s (''Grus canadensis'') and great blue heron
The great blue heron (''Ardea herodias'') is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North America and Central America, as well as the Caribbean and the Galápagos ...
s (''Ardea herodias'').
Reptiles
Early reports claimed relatively little predation of reptiles by red-tailed hawks but these were regionally biased towards the east coast and the upper Midwest of the United States.[Fisher, A. K. (1893). ''Hawks and owls of the United States in their relation to agriculture''. U.S. Dept. of Agriculture Bull. 3. Government Printing Office, Washington, D.C.] However, locally the predation on reptiles can be regionally quite heavy and they may become the primary prey where large, stable numbers of rodents and leporids are not to be found reliably. Nearly 80 species of reptilian prey have been recorded in the diet at this point.[ Most predation is on snakes, with more than 40 species known in the prey spectrum. The most often found reptilian species in the diet (and sixth overall in 27 North American dietary studies) was the ]gopher snake
''Pituophis'' is a genus of nonvenomous colubrid snakes, commonly referred to as gopher snakes, pine snakes, and bullsnakes, which are endemic to North America.
Geographic range
Species and subspecies within the genus ''Pituophis'' are found ...
(''Pituophis catenifer''). Red-tails are efficient predators of these large snakes, which average about in adults, although they also take many small and young gopher snakes. Along the Columbia River
The Columbia River (Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, C ...