Killdeer

The killdeer is a tall and slender plover, with a relatively long tail. Adults ranging in length from 20 to 28 cm (7.9 to 11.0 in), having a wingspan between 59 and 63 cm (23 and 25 in), and usually being between 72 and 121 g (2.5 and 4.3 oz) in weight. It has a short, thick, and dark bill, flesh-colored legs, and a red eye ring.

Its upper parts are mostly brown with rufous fringes, its cap, back, and wings being the former color. It has a white forehead and a white stripe behind the eye, and its lores and the upper borders to the white forehead are black. The killdeer also has a white collar with a black upper border. The rest of the face is brown. The breast and belly are white, except for two black breast bands. It is the only plover in North America with two breast bands. The rump is red, and the tail is mostly brown. The latter also has a black subterminal band, a white terminal band, and barred white feathers on the outer portion of the tail. A white wing stripe at the base of the flight feathers is visible in flight. The female's mask and breast bands tend to be browner than those of the male. The adult of the subspecies C. v. ternominatus is smaller, paler, and greyer than the nominate. The subspecies C. v. peruvianus is smaller than the nominate and has more extensive rufous feather fringes. The juvenile is similar to the adult. …

The nominate subspecies of the killdeer breeds in the US (including southeastern Alaska), southern Canada, and Mexico, with less widespread grounds further south, to Panama. Some northern populations are migratory. This bird is resident in the southern half of its breeding range, found throughout the year in most of the contiguous United States. It also winters south to Central America, the West Indies, Colombia, Ecuador, and islands off Venezuela, leaving its breeding grounds after mid-July, with migration peaking from August to September. Migration to the breeding grounds starts in February and ends in mid-May. The subspecies C. v. ternominatus is thought to be resident in the Bahamas, Greater Antilles, and Virgin Islands. C. v. peruvianus is seen year-round in western Ecuador, Peru, and extreme northwestern Chile. The killdeer uses beach habitats, coastal wetlands, and fields during the non-breeding season. It forages almost exclusively in these fields, especially those with short vegetation and with cattle (which likely shorten the vegetation) and standing water. When breeding, the killdeer has a home range of about 6 ha (15 acres), although this is generally larger when nesting more than 50 m (160 ft) away from water. Although generally a low-land species, it is found up to the snowline in meadows and open lakeshores during its autumn migration.

The killdeer feeds primarily on insects (especially beetles and flies), in addition to millipedes, worms, snails, spiders, and some seeds. It opportunistically takes tree frogs and dead minnows. It forages almost exclusively in fields (no matter the tide), especially those with short vegetation and with cattle (which likely shorten the vegetation) and standing water. Standing water alone does not have a significant effect on field choice unless combined with cattle. Viable disseminules can be recovered from killdeer feces, indicating that this bird is important in transporting aquatic organisms. The killdeer uses visual cues to forage. An example of this is "foot-trembling", where it stands on one foot, shaking the other in shallow water for about five seconds, pecking at any prey stirred up. When feeding in fields, it sometimes follows plows to take earthworms disturbed to the surface. The female forages significantly more than the male during most stages of breeding. The former feeds the most before and during egg-laying, the least when incubation starts (as little time to feed remains), with a return to high levels after. During the nonbreeding season, the killdeer forages during the night, depending on the lunar cycle. When the moon is full, it feeds more at night and roosts more during the day. …

The killdeer was described in 1758 by Swedish naturalist Carl Linnaeus in the 10th edition of his Systema Naturae as Charadrius vociferus, its current scientific name. Linnaeus' description was based on a 1731 account of it by English naturalist Mark Catesby in his The Natural History of Carolina, Florida and the Bahama Islands, where he called it the "chattering plover". The genus name Charadrius is Late Latin for a yellowish bird mentioned in the fourth-century Vulgate Bible. This word derives from the Ancient Greek kharadrios, a bird found in ravines and river valleys (kharadra, "ravine"). The specific name vociferus is Latin, coming from vox, "cry", and ferre, "to bear". Three subspecies are described:

C. v. vociferus Linnaeus, 1758 – The nominate subspecies (originally described subspecies), it is found in the US (including southeastern Alaska), southern Canada, Mexico, and with some less widespread grounds further south, to Panama. It winters to northwestern South America. C. v. ternominatus Bangs & Kennard, 1920 – This subspecies is found on the Bahamas, the Greater Antilles, and Virgin Islands. C. v. peruvianus (Chapman, 1920) – This South American subspecies is found in western Ecuador, Peru, and extreme northwest Chile. The killdeer's call resembles the phrase "kill deer", for which the species is named.