Coursers and Pratincoles
Coursers and Pratincoles
Coursers and the closely related pratincoles are 16 species of birds that comprise the family Glareolidae, in the order Charadriiformes, which also contains the plovers, sandpipers, and other families of waders and shore-birds. The pratincoles occur in southern Europe and Asia, Africa, Southeast Asia, and Australasia, but coursers only occur in Africa, the Middle East, and India.
Coursers and pratincoles breed in sandy or stony deserts, in grassy plains, or in savannas, but always near water. Both types of birds fly gracefully, using their long, pointed wings.
Coursers have relatively long legs, three toes on their feet, a square tail, and a relatively long, thin, somewhat down-curved beak. Coursers are nomadic during their non-breeding season, undertaking wanderings in unpredictable directions, as is the case of many other bird species that breed in deserts.
Pratincoles have shorter legs, four toes, a deeply forked tail, and a short bill with a wide gape. Pratincoles undertake long-distance migrations during the non-breeding season, usually in flocks. The sexes are similar in both of these types of birds.
Pratincoles largely prey on flying insects, much in the manner of swallows (an alternate common name for these birds is swallow-plover). They also feed on the ground, running after their prey with rapid, short bursts of speed. Coursers are also insectivorous, but they feed exclusively on terrestrial insects, which are caught on the run. Coursers will also eat seeds when they are available.
Pratincoles occur in groups and nest in large, loosely structured colonies. Coursers are less social than this and do not nest in colonies. The nests of coursers and pratincoles are simple scrapes made in the open. In most species there are two eggs in a clutch, which are incubated by both the female and the male parents. These birds mostly nest in hot habitats, so the purpose of incubation is often to keep the eggs cool, rather than warm as in most birds. Some species moisten their eggs to keep them cooler.
Young coursers and pratincoles are precocious, hatching with their eyes open and are able to walk one day after birth. However, they are led to a sheltering bush or other hiding place as soon as they are mobile, and they shelter there while the parents bring them food. The young birds are well camouflaged to blend in with their surroundings.
If a predator is near the nest or babies, adult pratincoles will perform injury-feigning distraction displays meant to lure the animal away. Both coursers and pratincoles also have startle displays that they deploy under these conditions, in which the wings and tail are raised suddenly to reveal bold patterns of coloration in an attempt to unnerve the predator.
Species of coursers
The double-banded courser (Rhinoptilus africa-nus ) of Africa lays only one egg, and the nest is commonly located near antelope dung as an aid to camouflage. The nest of the three-banded courser (R. cinctus ) of Africa is a relatively deep scrape in which the clutch of two eggs is two-thirds buried in sand during incubation. The Egyptian plover (Pluvialis aegyptius ) is a courser that breeds along large rivers in central and northeastern Africa. This species also buries its eggs and even its babies, and it also regurgitates water to cool these down on especially hot afternoons.
Species of pratincoles
The collared pratincole, red-winged pratincole, or swallow plover (Glareola pratincola ) is highly unusual in having migratory populations in both the southern and northern hemispheres. Northern birds breed in open steppes, savannas, and dry mudflats in southern Europe and southwestern Asia, and winter in Africa. Birds that breed in southern Africa, migrate to northern Africa to spend their non-breeding season. The black-winged pratincole (G. nordmanni ) is a widespread species that breeds from southeastern Europe through central Asia, and winters on tropical shores in south and Southeast Asia. The oriental pratincole (G. maldivarum ) breeds in central and southern Asia, and migrates as far south as Australia.
The Australian pratincole (Stiltia isabella ) breeds widely across much of that island continent, including the semi-arid interior. This species migrates north to spend its non-breeding season in the coastal tropics, from northern Australia to Indonesia. This is the only species in its genus, and it is rather intermediate in form to the coursers and pratincoles. Like the coursers, the Australian pratincole has a relatively long beak and long legs, a short tail, and no hind toe. In addition, this species does not have comb-like structures called pectinations on the claw of the middle toe, a characteristic that all other pratincoles and the coursers exhibit.
Resources
BOOKS
Bird Families of the World. Oxford: Oxford University Press, 1998.
Brooke, M., and T. Birkhead. The Cambridge Encyclopedia of Ornithology. Cambridge, U.K.: Cambridge University Press, 1991.
Maclean, G.L. “Family Glareolidae (Coursers and Pratincoles).” In Handbook of the Birds of the World, edited by J. del Hoyo, A. Elliott, and J. Sargatal. Barcelona: Lynx Edicions, 1996.
Prater, T., P. Hayman, and J. Marchant. Shorebirds: An Identification Guide to the Waders of the World. New York: Houghton Mifflin, 1991.
Bill Freedman