The hen harrier (''Circus cyaneus'') 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 ...
. It breeds in
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
It
migrates to more southerly areas in winter. Eurasian birds move to southern Europe and southern temperate Asia. In the mildest regions, such as France and
Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
, hen harriers may be present all year, but the higher ground is largely deserted in winter.
The
northern harrier
The northern harrier (''Circus hudsonius''), or ring-tailed hawk, is a bird of prey. It breeds throughout the northern parts of the northern hemisphere in Canada and the northernmost USA.
The northern harrier migrates to more southerly areas ...
was formerly considered to be a
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 ...
of the hen harrier.
Taxonomy
In 1758 the English naturalist
George Edwards included an illustration and a description of the hen harrier in the first volume of his ''Gleanings of Natural History''. He used the English name "The blue hawk". Edwards based his hand-coloured etching on a bird that had been shot near London. When in 1766 the Swedish naturalist
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...
updated his ''
Systema Naturae
' (originally in Latin written ' with the ligature æ) is one of the major works of the Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the system, now known as binomial nomen ...
'' for the
twelfth edition, he placed the hen harrier with the falcons and eagles 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 ...
''
Falco''. Linnaeus included a brief description, coined 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 cyaneus'' and cited Edwards' work. The hen harrier is now placed in the genus ''
Circus
A circus is a company of performers who put on diverse entertainment shows that may include clowns, acrobats, trained animals, trapeze acts, musicians, dancers, hoopers, tightrope walkers, jugglers, magicians, ventriloquists, and unicyclist ...
'' that was introduced by the 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 genus name ''Circus'' is derived from the
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
''kirkos'', referring to a bird of prey named for its circling flight (''kirkos'', "circle"). The specific epithet ''cyaneus'' is from
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
and means "dark blue". The species is
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...
: no
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 ...
are recognised.
[
The hen harrier was formerly considered to be ]conspecific
Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species.
Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organ ...
with the northern harrier
The northern harrier (''Circus hudsonius''), or ring-tailed hawk, is a bird of prey. It breeds throughout the northern parts of the northern hemisphere in Canada and the northernmost USA.
The northern harrier migrates to more southerly areas ...
.[
]
Description
The hen harrier is [ long with a wingspan.][ It resembles other harriers in having distinct male and female plumages. The sexes also differ in weight, with males weighing , with an average of , and females weighing , with an average of .][ Among standard measurements, the wing chord is , the ]tail
The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...
is and the tarsus is .[ It is relatively long winged and long tailed.][
The male is mainly grey above and white below except for the upper breast, which is grey like the upperparts, and the rump, which is white; the wings are grey with black wingtips. The female is brown above with white upper tail coverts, hence females, and the similar juveniles, are often called "ringtails". Their underparts are buff streaked with brown.][ Immatures look like females but with less distinct barring, dark brown secondaries dark brown and less-streaked belly.
The female gives a whistled ''piih-eh'' when receiving food from the male, and her alarm call is ''chit-it-it-it-it-et-it''. The male calls ''chek-chek-chek'', with a more bouncing ''chuk-uk-uk-uk'' during his display flight.][
]
Behaviour
This medium-sized raptor
Raptor or RAPTOR may refer to:
Animals
The word "raptor" refers to several groups of bird-like dinosaurs which primarily capture and subdue/kill prey with their talons.
* Raptor (bird) or bird of prey, a bird that primarily hunts and feeds on v ...
breeds on moorland
Moorland or moor is a type of habitat found in upland areas in temperate grasslands, savannas, and shrublands and montane grasslands and shrublands biomes, characterised by low-growing vegetation on acidic soils. Moorland, nowadays, generally ...
, 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 ...
s, 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, farm
A farm (also called an agricultural holding) is an area of land that is devoted primarily to agricultural processes with the primary objective of producing food and other crops; it is the basic facility in food production. The name is used fo ...
land coastal prairies, marsh
A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at ...
es, 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, swamp
A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...
s and other assorted open areas. A male will maintain a territory averaging , though male territories have ranged from .
These, are the one of the few raptorial birds known to practice polygyny
Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women.
Incidence
Polygyny is more widespread in Africa than in any o ...
– one male mates with several females. Up to five females have been known to mate with one male in a season. A supplementary feeding experiment on the Orkney islands showed that rates of polygyny were influenced by food levels; males provided with extra food had more breeding females than 'control' males that received no extra food.
The nest is built on the ground or on a mound of dirt or vegetation. Nests are made of sticks and are lined inside with grass and leaves. Four to eight (exceptionally 2 to 10) whitish eggs
Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...
are laid. The eggs measure approximately . The eggs are incubated mostly by the female for 31 to 32 days. When incubating eggs, the female sits on the nest while the male hunts and brings food to her and the chicks. The male will help feed chicks after they hatch, but does not usually watch them for a greater period of time than around 5 minutes. The male usually passes off food to the female, which she then feeds to the young, although later the female will capture food and simply drop into the nest for her nestlings to eat. The chicks fledge at around 36 days old, though breeding maturity is not reached until 2 years in females and 3 years in males.
In winter, the hen harrier is a bird of open country, and will then roost communally, often with merlins and marsh harrier
The marsh harriers are birds of prey of the harrier subfamily. They are medium-sized raptors and the largest and broadest-winged harriers. Most of them are associated with marshland and dense reedbeds. They are found almost worldwide, excluding o ...
s. There is now an accepted record of transatlantic vagrancy by the northern harrier, with a juvenile being recorded in Scilly
The Isles of Scilly (; kw, Syllan, ', or ) is an archipelago off the southwestern tip of Cornwall, England. One of the islands, St Agnes, is the most southerly point in Britain, being over further south than the most southerly point of the ...
, Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
from October 1982 to June 1983.[
]
Hunting behaviour
This is a typical harrier, which hunts on long wings held in a shallow V in its low flight during which the bird closely hugs the contours of the land below it. Northern or hen harriers hunt primarily 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, as do most harriers. Up to 95% of the diet comprises small mammals. However, 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 are hunted with some regularity as well, especially by males. Preferred avian prey include 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 open country (i.e. sparrows, lark
Larks are passerine birds of the family Alaudidae. Larks have a cosmopolitan distribution with the largest number of species occurring in Africa. Only a single species, the horned lark, occurs in North America, and only Horsfield's bush lark occu ...
s, pipit
The pipits are a Cosmopolitan distribution, cosmopolitan genus, ''Anthus'', of small passerine birds with medium to long tails. Along with the wagtails and longclaws, the pipits make up the family (biology), family Motacillidae. The genus is wide ...
s), small shorebird
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 ...
s and the young 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 ...
and 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 ...
. Supplementing the diet occasionally are 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 (especially frog
A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...
s), reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...
s and insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s (especially orthoptera
Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – grassho ...
ns).[ The species has been observed to hunt ]bat
Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most bi ...
s if these are available. Larger prey, such as rabbit
Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...
s and adult 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 are taken sometimes and harriers have been known to subdue these by drowning them in water.[ Harriers hunt by surprising prey while flying low to the ground in open areas, as they drift low over fields and moors.][ The harriers circle an area several times listening and looking for prey. Harriers use hearing regularly to find prey, as they have exceptionally good hearing for diurnal raptors, this being the function of their ]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 ...
-like facial disc.[ This harrier tends to be a very vocal bird while it glides over its hunting ground.
]
Mortality and competition
Little information is available on longevity in hen harriers. The longest-lived known bird is 16 years and 5 months. However, adults rarely live more than 8 years. Early mortality mainly results from predation. Predators of eggs and nestlings include 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 ...
s, skunk
Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or ginge ...
s, badger
Badgers are short-legged omnivores in the family Mustelidae (which also includes the otters, wolverines, martens, minks, polecats, weasels, and ferrets). Badgers are a polyphyletic rather than a natural taxonomic grouping, being united b ...
s, fox
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 ...
es, crows and ravens, dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s and 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. Both parents attack potential predators with alarm calls and striking with talons. Short-eared owl
The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...
s are natural competitors of this species that favor the same prey and habitat, as well as having a similarly broad distribution. Occasionally, both harriers and short-eared owls will harass each other until the victim drops its prey and it can be stolen, a practice known as kleptoparasitism
Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when foo ...
. Most commonly, the harriers are the aggressors pirating prey from owls.[
]
Status
This species has a large range. There is evidence of a population decline, but the species is not believed to be approaching the thresholds for the population decline criterion of the IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
(i.e., declining more than 30% in ten years or three generations). It is therefore classified as "least concern". In the United Kingdom, however, hen harrier populations are in a critical condition, due to habitat loss and illegal killing on grouse moor
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 mitochondria ...
s. In 2012 only 617 pairs remained, representing a fall of 20% from 2004.
Relationship with humans
In some parts of Europe people believed that seeing a harrier perched on a house was a sign that three people would die. Unlike many raptors, hen harriers have historically been favorably regarded by farmers because they eat predators of quail eggs and mice that damage crops. Harriers are sometimes called "good hawks" because they pose no threat to poultry as some hawks do.
Forestry and hen harriers
The hen harrier is a bird of open habitats such as heather moorland and extensive agriculture. However, much of its range, particularly in Ireland and parts of western Britain, has been (and continues to be) afforested, predominantly with non-native conifers such as Sitka spruce
''Picea sitchensis'', the Sitka spruce, is a large, coniferous, evergreen tree growing to almost tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth-larg ...
(''Picea sitchensis'') from North America.[ Hen harriers nest and forage in commercial forestry when it is young, before the canopy closes (typically at between 9–12 and years old), but do not make much use of thicket and subsequent growth stages,][ which typically comprise between and of the commercial growth cycle. Where forests replace habitats that were used by hen harriers they will therefore tend to reduce overall habitat availability.][ However, where afforestation takes place in areas that were previously underutilised by hen harriers, it may increase the value of such areas to this species in the long-term.][ Areas dominated by forestry may remain suitable to hen harriers provided that a mosaic of age classes is maintained within the forest, such that areas of young, pre-thicket forest are always available.
]
References
External links
The Langholm Moor Demonstration Project
Field Guide Page on Flickr
(in Persian)
Ageing and sexing (PDF; 4.3 MB) by Javier Blasco-Zumeta & Gerd-Michael Heinze
*
RSPB Skydancer website
*
*
{{DEFAULTSORT:harrier, hen
hen harrier
The hen harrier (''Circus cyaneus'') is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
It migrates to more southerly areas in winter. Eurasian birds move to southern Eur ...
Birds of prey of Eurasia
hen harrier
The hen harrier (''Circus cyaneus'') is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
It migrates to more southerly areas in winter. Eurasian birds move to southern Eur ...
hen harrier
The hen harrier (''Circus cyaneus'') is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
It migrates to more southerly areas in winter. Eurasian birds move to southern Eur ...