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Birds of prey or predatory birds, also known as (although not the same as) raptors, are hypercarnivorous bird species that actively hunt and feed on other vertebrates (mainly mammals, reptiles and other smaller birds).
Experiments on blue jays suggest they form a search image for certain prey.. Visual predators may form what is termed a search image of certain prey.. Predators need not locate their host directly: Kestrels, for instance, are able to detect the faeces and urine of their prey (which reflect ultraviolet), allowing them to identify areas where there are large numbers of voles, for example.
About one half of bird species with fovea have a single one, but uniquely in birds, [221] some, such as terns, kingfishers and hummingbirds, have a second fovea, [222] called the temporal fovea, that assists in judging speed and distance and increases visual acuity. Birds that do not have a second fovea will sometimes bob their head to improve ...
Birds of prey have a very high density of receptors and other adaptations that maximise visual acuity. The placement of their eyes gives them good binocular vision enabling accurate judgement of distances. Nocturnal species have tubular eyes, low numbers of colour detectors, but a high density of rod cells which function well in poor light.
The blue jay can be beneficial to other bird species, as it may chase predatory birds, such as hawks and owls, and will scream if it sees a predator within its territory. It has also been known to sound an alarm call when hawks or other dangers are near, and smaller birds often recognize this call and hide themselves away accordingly.
The span between precocial and altricial species is particularly broad in the biology of birds. Precocial birds hatch with their eyes open and are covered with downy feathers that are soon replaced by adult-type feathers. [17] Birds of this kind can also swim and run much sooner after hatching than altricial young, such as songbirds. [17]
Unlike other species, turacos owe their color to a copper-based pigment called turacoverdin. The common grackle and many shimmering hummingbirds display iridescence like the way a prism splits ...
Kite is the common name for certain birds of prey in the family Accipitridae, particularly in the subfamilies Elaninae and Perninae and certain genera within Buteoninae. [1] The term is derived from Old English cȳta (“kite; bittern”), [2] possibly from the onomatopoeic Proto-Indo-European root *gū- , "screech." [3] [4]