Семейство ястребиных птиц

Family of birds of prey

The Accipitridae (,/æ//k//s//ɪ/'/p//ɪ//t//r//ɪ//d//iː//, // //d//eɪ/) is one of the three families within the order Accipitriformes, and is a family of small to large birds of prey with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium sized mammals, with a number feeding on carrion and a few feeding on fruit. The Accipitridae have a cosmopolitan distribution, being found on all the world's continents (except Antarctica) and a number of oceanic island groups. Some species are migratory. The family contains 255 species which are divided into 70 genera. Many well known birds such as hawks, eagles, kites, harriers and Old World vultures are included in this group. The osprey is usually placed in a separate family (Pandionidae), as is the secretary bird (Sagittariidae), and the New World vultures are also usually now regarded as a separate family or order. Karyotype data indicate the accipitrids analysed are indeed a distinct monophyletic group.

The accipitrids have been variously divided into some five to ten subfamilies. Most share a very similar morphology, but many of these groups contain taxa that are more aberrant. These are placed in their respective position more for lack of better evidence than anything else. The phylogenetic layout of the accipitrids has thus always been a matter of dispute. The accipitrids are recognizable by a peculiar rearrangement of their chromosomes. Apart from this, morphology and mtDNA cytochrome b sequence data give a confusing picture of these birds' inter relationships. The hawks, kites, eagles and Old World vultures as presently assigned in all likelihood do not form monophyletic groups. According to the molecular data, the Buteoninae are most likely poly or paraphyletic, with the true eagles, the sea eagles, and the buteonine hawks apparently representing distinct lineages. These appear to form a group with the Milvinae, Accipitrinae and Circinae, but the exact relationships between the lineages are not robustly resolvable. The Perninae and possibly the Elaninae are older lineages, as are the Old World vultures. The latter are likely also poly or paraphyletic, with some aberrant species like the bearded and Egyptian vultures standing apart from the naked necked "true" vultures.

Accipitrids are predominantly predators and most species actively hunt for their prey. Prey is usually captured and killed in the powerful talons of the raptor and then carried off to be torn apart with a hooked bill for eating or feeding to nestlings. A majority of accipitrids are opportunistic predators that will take any prey that they can kill. However, most have a preference for a certain type of prey, which in harriers and the numerous buteonine hawks (including more than 30 species in the genus Buteo) tends towards small mammals such as rodents. Among the raptors that mainly favor small mammals, harriers generally hunt by hovering over openings until they detect their prey and descend upon them. Due to the specificity of their hunting style, prey preferences, and habitat preferences, usually only one harrier species tends to be found per region. Buteonine hawks usually watch for prey from a perch but most species will also readily hunt on the wing, including from a high soar. Many buteonines are amongst the most generalized feeders, often feeding on any active small animal they find, and will generally eat whatever diurnal rodent or lagomorph is most locally common. Some buteonines, however, are more specialized, such as certain species in the genus Buteogallus, which have evolved to specialize in feeding on crabs. Larger Buteogallus, namely the solitary eagles, and Geranoaetus are much larger than other buteonines and seem to have become avian apex predators of specific habitat niches—for example, savanna, cloud forest and páramo in South America—and are thus honorary "eagles". In Accipiter hawks (the most species rich accipitrid genus with nearly 50 extant species), prey is mainly other birds. Accipiters are in general forest and thicket dwelling species. Accipiter hawks usually ambush birds in dense vegetation, a dangerous hunting method that requires great agility. Many smaller tropical species of Accipiter eat nearly equal portions of insects and reptiles and amphibians as they do of birds while some of the larger species have become more generalized and may feed extensively on rodents and lagomorphs, as well as other various non avian animals. Most accipitrids will supplement their diet with non putrid carrion, but none are specialized for this as well as the 14–16 species of vultures, which have evolved very large bodies (which leave them equipped to fill their crop with carrion); weaker, less specialized feet than other accipitrids; large wingspans to spend long periods of time in flight over openings scanning for carcasses; and complex social behavior in order to establish a mixed species hierarchy at carrion. The New World vultures have attained several similar characteristics, but only through convergent evolution, and are seemingly not directly related to Old World vultures and other accipitrids. The lammergeier (Gypaetus barbatus) is an aberrant cousin of the Old World vultures that has maintained strong feet that it uses to carry and drop large bones in order to crack them open to feed on bone marrow, their primary food, a technique they also sometimes use for live prey items, like tortoises. A few species may opportunistically feed on fruit. In one species, the palm nut vulture (Gypohierax angolensis) (possibly not closely related to other "vultures"), it may form more than half of the diet. "Eagles" are several raptors that are not necessarily closely related, but can be broadly defined by large body size (larger than other raptors, excluding vultures) and the taking of typically larger prey, including mid sized mammals and larger birds. The most diverse group of eagles is the "booted eagles", a variable group of about 38 species defined by their feathering covering their legs (shared by only a couple of buteonine species). Most accipitrids usually hunt prey smaller than themselves. However, many accipitrids of almost all sizes have been recorded as capturing and then flying with prey of equal weight or even slightly heavier than themselves in their talons, a feat that requires great strength. Occasionally, an eagle or other raptor that kills prey considerably heavier than itself (too heavy for the raptor to carry and fly with) will then have to leave prey at the site of the kill and later return repeatedly to feed or dismember and bring to a perch or nest piece by piece. This has the advantage of providing a surplus of food but has the disadvantage of potentially attracting scavengers or other predators which can steal the kill or even attack the feeding accipitrid. Using this method, accipitrids such as the golden eagle (Aquila chrysaetos), wedge tailed eagle (Aquila audax), martial eagle (Polemaetus bellicosus) and crowned eagle (Stephanoaetus coronatus) have successfully hunted ungulates, such as deer and antelope, and other large animals (kangaroos and emus in the wedge tailed) weighing more than 30 kg (66 lb), 7–8 times their own mass. More typical prey for these powerful booted eagle species weigh between
The Haliaeetus eagles and the osprey (Pandion haliaetus) mainly prefer to prey on fish, which comprising more than 90% of food for the osprey and some fish eagles. These large acciptrids may supplement their diets with aquatic animals other than fish, especially sea eagles, which also hunt large numbers of water birds and are expert kleptoparasites. Reptiles and amphibians are hunted by almost all variety of acciptrids when the opportunity arises and may be favored over other prey by some eagles, i. e. Spizaetus hawk eagles and the "eagles" in Buteogallus, and several species of buteonine hawks found in the tropics. Bazas and forest hawks in the genus Accipiter may take reptiles from trees whilst other species may hunt them on the ground. Snakes are the primary prey of the snake eagles (Circaetus) and serpent eagles (Spilornis and Dryotriorchis). The mammal hunting, huge and endangered Philippine eagle (Pithecophaga jefferyi) is most closely related to the snake eagles. Another striking aberration of the snake eagle lineage is the bateleur (Terathopius ecaudatus), which has evolved unusually bright plumage in adults, with a huge red cere, red feet, bright yellow bill, and boldly contrasting grey and white markings over black plumage. The bateleur feeds extensively on carrion and almost any other feeding opportunity that presents itself.

In terms of their reproductive biology and socio sexual behavior, accipitrids share many characteristics with other extant groups of birds that appear not be directly related, but all of which have evolved to become active predators of other warm blooded creatures. Some of the characteristics shared with these other groups, including falcons, owls, skuas and shrikes, are sexual dimorphism in size, with the female typically larger than the male; extreme devotion of breeding pairs to each other or to a dedicated nesting site; strict and often ferocious territorial behavior; and, on hatching, occasional competition amongst nestlings, including regular siblicide in several species. Before the onset of the nesting season, adult accipitrids often devote a majority of their time to excluding other members of their own species and even of other species from their nesting territories. In several species, this occurs by territorial display flights over the border of their breeding ranges. In several forest dwelling varieties, however, vocalizations are used to establish territories. Due to the density of the habitat, display flights are apparently impractical. While a single devoted breeding pair is considered typical, research has revealed that in varied accipitrids, multiple birds engaging in nesting behavior is more commonly than previously thought. Some harriers have evolved to become polygynous, with a single smaller male breeding with and then helping multiple females raise young. The most extreme known species of accipitrid in terms of sociality is the Harris's hawks (Parabuteo unicinctus), which up to seven fully grown birds may hunt, nest and brood cooperatively, with the extra birds typically being prior years' offspring of the breeding pair. Unlike the other two larger groups of raptorial birds, the owls and most falcons, accipitrids typically build their own nest. Nest sites are typically in relatively secure places, such as the crook of a large tree or an ample cliff ledge, and can vary in elevation from the flat ground of prairies or steppe to near the peaks of the tallest mountains. Accipitrids will readily return to use a nest site repeatedly, which has resulted in several of the largest bird's nests known, as a single nest may see decades of use, with more material added each breeding season. The single largest known tree nest known for any animal, belonging to a bald eagle (Haliaeetus leucocephalus), was found to be deep and across, and to weigh Some species, especially eagles, will build multiple nests for use in alternating years. Although they usually use nests they build themselves, accipitrids sometimes use abandoned nests build by other animals or pirate nests from other birds, typically other types of accipitrid. Compared to most other types of birds, the stretch from egg laying to independence in young birds is prolonged. In accipitrids, the breeding season ranges from about two to three months to roughly a year and a half, the latter in some of the larger tropical eagles. Species inhabiting temperate ranges as a rule have shorter breeding seasons due to the shorter stretches of warm weather that facilitates ready capture of prey. Usually from 2 to 6 eggs are laid in accipitrids, a relatively small clutch, and some species may lay only one egg. In almost all accipitrids, eggs are laid at intervals rather than all at once and in some larger species the intervals can be several days. This results in one of the hatchlings being larger and more advanced in development than its siblings. The benefits of siblicide, which is at least occasionally recorded in many species and almost always occurs in some, such as tropical members of the booted eagle group, is that the smaller siblings are a kind of insurance policy that if the oldest, strongest nestling dies, one of the smaller siblings may take its place. In most species that have displayed siblicide, times of food plenty may result in two or more the nestlings being successfully raised to fledging. In most accipitrids, the smaller males typically obtain food both for the incubating and brooding female and the nestlings. Males, however, occasionally take a shift incubating or even more sporadically brooding the nestlings, which allows the female to hunt. Most accipitrids feed their nestlings strips of meat or whole prey items, but most vultures feed their nestlings via regurgitation. Fledging often takes considerable effort for young birds and may take several weeks as opposed to days in many other types of birds. Once independent of their parents, young accipitrids often most wander for considerable stretches of time, ranging from 1 to 5 years, before they attain maturity. Most accipitrids have distinct plumages in their immature stage, which presumably serves as a visual cue to others of their species and may allow them to avoid territorial fights. Shortly after attaining mature plumages, pairs form, with a male typically displaying, often in flight but sometimes vocally, to win over a female. Many accipitrids breed with the same mate for several years or for life, although this is not the case for all species and, if a mate dies, the widowed bird will typically try to find another mate the next breeding season.