|Kingdom: Animalia Phylum: Chordata Class: Aves (Birds) Order: Charadriiformes Family: Burhinidae|
All Thick-knees (birds belonging to Burhinidae family), are long-legged and have three short, thick toes and a pointed bill. All Thick-knees have a round head on a slim-waisted neck, a broad, bulky body, and long tails that are narrow and tapered when closed and held pointing slightly downwards. Strikingly large, round eyes, a pale bill base, and various combinations of stripes above, through, and below each eye create bold plumage patterns. The head stripes are quite conspicuous at long range, but the piercing eye is most arresting up close. A wide iris contracts greatly in poor light to open a very large pupil but makes a vivid yellow or amber disk in bright sun.
Plumages are pale and sandy brown with white undersides; most thick-knees have a dark-edged, pale panel across the folded wing. Wing patterns are streaked, spotted, or plain, but in flight all reveal black-and-white patterns above and below the wings and tail. Sexes are almost alike and juvenal plumages are similar to those of adults. Downy chicks’ complex patterns mimic stony, sandy ground.
The Burhinus Thick-knees being crepuscular become active at dusk, having stayed quiet and immobile by day. They call loudly as night approaches, with far-carrying, strident, or fluty calls. As pairs fly to feeding places their bold wing patterns show well in fading light. Stone-curlews breed in isolation or in loose groups where limited habitat concentrates a few pairs. They are mostly solitary except when gathering to molt just before autumn migration. In midday heat, they frequently find deep shade beneath bushes and are difficult to find. Great thick-knees tend to avoid open sand and resort to rocks, stony banks, and muddy places along rivers or around large lakes; they are mostly active by night. Beach thick-knees are mostly seen by day, but it is not clear when they are most active.
All Thick-knees are terrestrial birds and perch no higher than on a fallen log or rock (except for Senegal Thick-knee). They fly low but strongly when moving between nesting and feeding places or if disturbed; otherwise, they are ground-dwelling birds. Courtship and territorial aggression are ground activities with loud calls, presumably because their nocturnal nature precludes extensive display flights. If undisturbed, a Thick-knee may rest on its tarsi, or stand with its body markedly sloping, tail down, head withdrawn into the shoulders, but a long-striding, feeding bird has a special elegance, if a somewhat furtive character. Nests are mere scrapes in soft earth, selected by the pair as they bow together towards the preferred spot.
Burhinidae consists of two genera (Burhinus and Esacus) and a total of nine species. Three species, all belonging to the Genus Burhinus, are found in India: