Peale's falcon | |
---|---|
Female | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Falconiformes |
Family: | Falconidae |
Genus: | Falco |
Species: | |
Subspecies: | F. p. pealei |
Trinomial name | |
Falco peregrinus pealei Ridgway, 1873 |
Peale's falcon (Falco peregrinus pealei) is a subspecies of the peregrine falcon. This subspecies was first identified by the ornithologist Robert Ridgway in 1873, named in honor of Titian Ramsay Peale. These birds are the largest subspecies of peregrines (on average) anywhere in the world.
Measurements for male F. p. pealei are as follows: length 16.3 inches (41 cm), wingspan 36.2 inches (92 cm), wing chord 12.60–13.58 in (320–345 mm). For females: length 18.7 inches (47 cm), wingspan 43.6 inches (111 cm), wing chord 14.29–15.39 in (363–391 mm) [1]
Weight range for male F. p. pealei are 28.57–37.32 oz (810–1,058 g), averaging 33.65 oz (954 g); females range 43.88–56.33 oz (1,244–1,597 g), averaging 49.31 oz (1,398 g). [2]
The adults are generally identified by the presence of heavy horizontal barring across their abdomen, large "tear-drop" shaped markings on their breast (more pronounced in the females) extending up into the auriculars, a white, smokey-white, or grayish background color on the breast (as opposed to the salmon to orangish background color on most other subspecies), very broad malar stripe to a full dark cap, and wider, stronger mandibles than is commonly seen in the species as a whole.
Immature birds are overall very dark, with little to no buff-colored edging to the feathers of the mantle, nearly completely dark heads, and very heavily streaked ventral markings. Rectrices are usually unbarred. Feet and cere color varies from light blue to light yellow.
The breeding range of F. p. pealei is a rather linear one being entirely coastal in orientation. Starting in the western part of the range, the Commander Islands are generally thought to be the extent to which they exist in Russia. Although they are speculatively referenced as nesting on the Kamchatka Peninsula and possibly the northern Kurile Islands, no evidence has been provided to support these locations. From the Commander Islands eastward they are found throughout the Aleutian Islands to the Sanak Islands, Cherni Island, Deer Island, the Pavlof Islands, and the Shumagin Islands. This area constitutes the western sub-population of F. p. pealei and is an estimated 375–580 breeding pairs [3] strong in Alaskan territory and 20–25 pairs in Russian territory. This group has a very uniformly and densely distributed population, with roughly 5–8 miles (8.0–12.9 km) of coastline between each eyrie on average. [3] This group also has a tendency to be more uniform in morphology.
The Alexander Archipelago, Haida Gwaii, portions of the British Columbia coast, the outer coast of Vancouver Island, and the Olympic Peninsula make up the eastern sub-population of F. p. pealei. The highest density of peregrines anywhere in the world was recorded on Langara Island in the mid 1950s. Ten nests being occupied in a single small bay of only 7.5 mi (12.1 km) of coastline, and a total of 21 nests on the whole island. [2] Unfortunately this astounding concentration of peregrine falcons was intimately linked to the very robust local seabird population that has declined since the 1950s due to unknown factors. Possible culprits for the decline include introduced non-native predators of seabirds such as rats and raccoons, coupled with possible changes brought on by human activities in the oceanic food chain on which the seabird colonies depend. The peregrine population of Langara Island is now believed to be about 25% of what it once was. [4] The current population of the eastern sub-group of F. p. pealei is about 20 breeding pairs in Washington, about 100 pairs in British Columbia, and about another 100 pairs in the Alexander Archipelago.
Along the south side of the Alaska Peninsula, the Kodiak Islands, portions of Cook Inlet, the Kenai Peninsula, Prince William Sound, and eastward to Glacier Bay constitutes the central sub-population of F. p. pealei. This area is marked by a decidedly lower population density than either the eastern or western populations. This fact and the slightly different morphology of this sub-group has caused some confusion amongst researchers as to the validity of F. p. pealei existing within this range. [2] [5]
Within its range, Peale's falcon can be found on rough, rocky seashores, sea cliffs, seastacks, islands, islets, and beaches.
Peale's falcon concentrates on hunting Alcids, often nesting very near seabird colonies for this purpose. However, this is not necessary for a successful eyrie. A study on Amchitka Island from 1968 to 1973 found that an average of 18.6 eyries on the island were in no close proximity to seabird colonies, as no sizeable colonies existed on the island. [3] Instead, these large, robust birds fly out to sea to hunt up to 50 miles from land, rather than inland. This is an impressive physical feat, as peregrines are not able to rest floating on water as seabirds do. They must either eat their prey while flying, or carry it a very long way back to land to consume it. Preferred species on Amchitka consisted of: Crested auklet (Aethia cristatella), 26.48% of the diet's biomass; Ancient murrelet (Synthliboramphus antiquus), 17.18% of the biomass; and alcids as a group provided 65.52% of the biomass. [6]
Other important prey species that this specialized population of peregrines are fond of are fork-tailed storm petrels, Leach's storm petrels, and black-legged kittiwakes.
The tufted puffin, also known as crested puffin, is a relatively abundant medium-sized pelagic seabird in the auk family (Alcidae) found throughout the North Pacific Ocean. It is one of three species of puffin that make up the genus Fratercula and is easily recognizable by its thick red bill and yellow tufts.
The peregrine falcon, also known simply as the peregrine, and historically as the duck hawk in North America, is a cosmopolitan bird of prey (raptor) in the family Falconidae. A large, crow-sized falcon, it has a blue-grey back, barred white underparts, and a black head. The peregrine is renowned for its speed. It can reach over 320 km/h (200 mph) during its characteristic hunting stoop, making it the fastest member of the animal kingdom. According to a National Geographic TV program, the highest measured speed of a peregrine falcon is 389 km/h (242 mph). As is typical for bird-eating (avivore) raptors, peregrine falcons are sexually dimorphic, with females being considerably larger than males.
The merlin is a small species of falcon from the Northern Hemisphere, with numerous subspecies throughout North America and Eurasia. A bird of prey once known colloquially as a pigeon hawk in North America, the merlin breeds in the northern Holarctic; some migrate to subtropical and northern tropical regions in winter. Males typically have wingspans of 53–58 centimetres (21–23 in), with females being slightly larger. They are swift fliers and skilled hunters which specialize in preying on small birds in the size range of sparrows to quail. The merlin has for centuries been well regarded as a falconry bird. In recent decades merlin populations in North America have been significantly increasing, with some merlins becoming so well adapted to city life that they forgo migration.
The pelagic cormorant, also known as Baird's cormorant or violet-green cormorant, is a small member of the cormorant family Phalacrocoracidae. Analogous to other smallish cormorants, it is also called the pelagic shag occasionally. This seabird lives along the coasts of the northern Pacific; during winter it can also be found in the open ocean. Pelagic cormorants have relatively short wings due to their need for economical movement underwater, and consequently have the highest flight costs of any bird.
The pigeon guillemot is a species of bird in the auk family, Alcidae. One of three species in the genus Cepphus, it is most closely related to the spectacled guillemot. There are five subspecies of the pigeon guillemot; all subspecies, when in breeding plumage, are dark brown with a black iridescent sheen and a distinctive wing patch broken by a brown-black wedge. Its non-breeding plumage has mottled grey and black upperparts and white underparts. The long bill is black, as are the claws. The legs, feet, and inside of the mouth are red. It closely resembles the black guillemot, which is slightly smaller and lacks the dark wing wedge present in the pigeon guillemot.
The razorbill, razor-billed auk, or lesser auk is a North Atlantic colonial seabird and the only extant member of the genus Alca of the family Alcidae, the auks. It is the closest living relative of the extinct great auk.
The great horned owl, also known as the tiger owl or the hoot owl, is a large owl native to the Americas. It is an extremely adaptable bird with a vast range and is the most widely distributed true owl in the Americas. Its primary diet is rabbits and hares, rats and mice, and voles, although it freely hunts any animal it can overtake, including rodents and other small mammals, larger mid-sized mammals, birds, reptiles, amphibians, and invertebrates.
The sharp-shinned hawk or northern sharp-shinned hawk, commonly known as a sharpie, is a small hawk, with males being the smallest hawks in the United States and Canada, but with the species averaging larger than some Neotropical species, such as the tiny hawk. The taxonomy is far from resolved, with some authorities considering the southern taxa to represent three separate species: white-breasted hawk, plain-breasted hawk, and rufous-thighed hawk. The American Ornithological Society and some other checklists keeps all four variations conspecific.
The little auk or dovekie is a small auk, the only member of the genus Alle. Alle is the Sami name of the long-tailed duck; it is onomatopoeic and imitates the call of the drake duck. Linnaeus was not particularly familiar with the winter plumages of either the auk or the duck, and appears to have confused the two species. Other common names include rotch, rotche,, bullbird, and sea dove, although the latter sometimes refers to a relative of dovekies, the black guillemot.
The Aleutian tern is a migratory bird living in the subarctic region of the globe most of the year. It is frequently associated with the Arctic tern, which it closely resembles. While both species have a black cap, the Aleutian tern may be distinguished by its white forehead. During breeding season, the Arctic terns have bright red bills, feet, and legs while those of the Aleutian terns are black.
The Barbary falcon is a medium-sized falcon about the size of a crow. This bird of prey is mainly resident. It ranges from the Canary Islands eastwards across some parts of North Africa, the Middle East and Central Asia.
The saker falcon is a large falcon species. It breeds from Central Europe eastwards across the Palearctic to Manchuria. It is a partial migrant, which means that some part of the population is migratory, some part is not. In Europe, for example, a part of the juveniles are migrating, while adults are mostly resident. The European and West Asian migratory sakers spend the winter in the Sahel region. On migration, they cross the Middle East, the Arabian peninsula, and Pakistan, where they are exposed to illegal trapping. The migratory birds to the east from Altai Mountains spend the winter in the Qinghai-Tibet Plateau.
The marbled murrelet is a small seabird from the North Pacific. It is a member of the family Alcidae, which includes auklets, guillemots, murres and puffins. It nests in old-growth forests or on the ground at higher latitudes where trees cannot grow. The marbled murrelet has declined in number since humans began logging its nest trees in the latter half of the 19th century. The decline of the marbled murrelet and its association with old-growth forests, at least in the southern part of its range, have made it a flagship species in the forest preservation movement.
The bat falcon is a bird of prey in the family Falconidae, the falcons and caracaras. It is found in Mexico, Central America, Trinidad, and every mainland South American country except Chile and Uruguay.
Cassin's auklet is a small, chunky seabird that ranges widely in the North Pacific. It is the only species placed in the genus Ptychoramphus. It nests in small burrows and because of its presence on well studied islands in British Columbia and off California it is one of the better known auks. It is named for the American ornithologist John Cassin.
The prairie falcon is a medium-large sized falcon of western North America. It is about the size of a peregrine falcon or a crow, with an average length of 40 cm (16 in), wingspan of approximately 1 meter (40 in), and average weight of 720 g (1.6 lb). As in all falcons, females are noticeably bigger than males. Though a separate species from the peregrine, the prairie falcon is basically an arid environment divergence of the early peregrine falcon lineage, able to subsist on less food than the peregrine, and generally lighter in weight than a peregrine of similar wing span. Having evolved in a harsh desert environment with low prey density, the prairie falcon has developed into an aggressive and opportunistic hunter of a wide range of both mammal and bird prey. It will regularly take prey from the size of sparrows to approximately its own weight, and occasionally much larger. It is the only larger falcon native only to North America. It is resident from southern Canada, through western United States, and into northern Mexico. The prairie falcon is popular as a falconry bird, where with proper training it is regarded as being as effective as the more well known peregrine falcon.
The aplomado falcon is a medium-sized falcon of the Americas. The species' largest continuous range is in South America, but not in the deep interior Amazon Basin. It was long known as Falco fusco-coerulescens or Falco fuscocaerulescens, but these names are now believed to refer to the bat falcon. Its resemblance in shape to the hobbies accounts for its old name orange-chested hobby. Aplomado is an unusual Spanish word for "lead-colored", referring to the blue-grey areas of the plumage – an approximate English translation would be "plumbeous falcon". Spanish names for the species include halcón aplomado and halcón fajado ; in Brazil it is known as falcão-de-coleira.
The fork-tailed storm petrel is a small seabird of the storm petrel family Hydrobatidae. It is the second-most abundant and widespread storm petrel and is the only bird in its family that is bluish-grey in colour.
The Peregrine Fund is a non-profit organization founded in 1970 that conserves threatened and endangered birds of prey worldwide. The successful recovery of the peregrine falcon in the United States, which was removed from the U.S. Endangered Species List in 1999, enabled the organization to expand its mission to include other endangered raptors around the world. The Peregrine Fund is headquartered at its World Center for Birds of Prey in Boise, Idaho, on a 580-acre (2.3 km2) campus with breeding and research facilities, an administrative office, interpretive center, research library, and archives.
The gyrfalcon, the largest of the falcon species, is a bird of prey. The abbreviation gyr is also used. It breeds on Arctic coasts and tundra, and the islands of northern North America and the Eurosiberian region. It is mainly a resident there also, but some gyrfalcons disperse more widely after the breeding season, or in winter. Individual vagrancy can take birds for long distances. Its plumage varies with location, with birds being coloured from all-white to dark brown. These colour variations are called morphs. Like other falcons, it shows sexual dimorphism, with the female much larger than the male. For centuries, the gyrfalcon has been valued as a hunting bird. Typical prey includes the ptarmigan and waterfowl, which it may take in flight; it also takes fish and mammals.