bird of prey

An Osprey

Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases, the females are considerably larger than the males. The term "raptor" is derived from the Latin word "rapere" (meaning to seize or take by force) and may refer informally to all birds of prey, or specifically to the diurnal group.^[1]

Formal classification

Bald Eagle

The diurnal birds of prey are formally classified into five families:

• Accipitridae: hawks, eagles, buzzards, harriers, kites and Old World vultures
• Pandionidae: the Osprey (sometimes classified as subfamily Pandioninae of the previous family)
• Sagittariidae: the Secretary Bird
• Falconidae: falcons and caracaras
• Cathartidae: New world vultures including condors.

The nocturnal birds of prey - the owls - are classified separately as members of two extant families of the order Strigiformes:

• Strigidae: (typical owls)
• Tytonidae: (barn and bay owls).

The observation that otherwise unrelated bird groups may perform similar ecological roles and bear striking morphological similarities to one another is explained largely by the idea of convergent evolution.

The common names for various birds of prey are based on structure but many of the traditional names do not reflect the evolutionary relationships between the groups.

Variations in shape and size

• Eagles tend to be large birds with long, broad wings and massive feet. Booted eagles have legs and feet feathered to the toes and build very large stick nests.
• Ospreys a single species found worldwide, specializes in fish, and builds large stick nests.
• Kites have long wings and relatively weak legs. They spend much of their time soaring. They will take live vetebrate prey but mostly feed on insects or even carrion.
• The true Hawks are medium-sized birds of prey that usually belong to the genus Accipiter (see below). They are mainly woodland birds that hunt by sudden dashes from a concealed perch. They usually have long tails for tight steering.
• Buzzards are medium-large raptors with robust bodies and broad wings, or, alternatively, any bird of the genus Buteo (also commonly known as "hawks" in North America).
• Harriers are large, slender hawk-like birds with long tails and long thin legs. Most hunt small vertebrates with a combination of keen eyesight and hearing, gliding and circling low over grasslands and marshes on their long broad wings.
• Vultures are carrion-eating raptors of two distinct biological families, each occurring in only the Eastern Hemisphere (Accipitridae) or the Western (Cathartidae). Members of both groups have heads either partly or fully devoid of feathers.
• Falcons are small to medium sized birds of prey with long pointed wings. Unlike most other raptors, they belong to the Falconidae rather than the Accipitridae. Many are particularly swift flyers. Instead of building their own nests, falcons appropriate old nests of other birds but sometimes they lay their eggs on cliff ledges or in tree hollows. Caracaras are a distinct subgroup of the Falconidae unique to the New World, and most common in the Neotropics - broad wings, naked faces and the appetites of a generalist suggest some level of convergence with either the Buteos or the vulturine birds, or both.
• Owls are variable-sized, typically night-specialized hunting birds. They fly soundlessly and have very acute senses of hearing and low-light vision.

Birds of prey and game preservation

In Britain birds of prey were very badly affected by being shot by gamekeepers as "vermin" during the heyday of game preservation in the 18th and 19th centuries: for example, in 3 years in the 19th century gamekeepers' records in the Glengarry Estate in Scotland record killing^[2]:

• Mammals: 11 foxes, 198 wildcats, 246 martens, 106 polecats, 67 badgers, 301 stoats and weasels, 46 otters, 78 house cats
• Birds of prey: 27 white-tailed sea eagles, 15 golden eagles, 3 honey buzzards, 18 ospreys, 63 goshawks, 285 common buzzards, 371 rough-legged buzzards, 83 hen harriers, 5 marsh harriers, 98 "blue hawks" (?= peregrine falcons), 7 orange-legged falcons, 275 kites, 11 hobby hawks, 78 merlin hawks, 6 gyr falcons, 462 kestrels, 35 "horned owls", 71 "fern owls" (?= short-eared owls)
• Other birds: 1431 hooded crows, 475 ravens, 8 magpies

Notes

References

• Remsen, J. V., Jr., C. D. Cadena, A. Jaramillo, M. Nores, J. F. Pacheco, M. B. Robbins, T. S. Schulenberg, F. G. Stiles, D. F. Stotz, and K. J. Zimmer. [Version 2007-04-05.] A classification of the bird species of South America. American Ornithologists' Union. Accessed 2007-04-10.

External links

• Explore Birds of Prey with The Peregrine Fund
• Videos of birds of prey on the Internet Bird Collection
• Bird of Prey Pictures
• Global Raptor Information Network
• The Arboretum at Flagstaff's Wild Birds of Prey Program