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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or stand with its body markedly sloping, tail down, head withdrawn into the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:
Beach Thick-knee (Burhinus giganteus) - local resident
Eurasian Thick-knee (Burhinus oedicnemus) - widespread resident
Great Thick-knee (Burhinus recurvirostris) - widespread resident |
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