(2070) Chlidonias leucoptera leucoptera.
THE WHITE-WINGED BLACK TERN.
Sterna leucoptera Temm., Man. d'Orn., p. 483 (1815) (Mediterranean). Hydrochelidon leucoptera. Blanf. & Oates, iv, p. 308.
Vernacular names. None recorded.
Description. Whole head, neck, lower parts to the vent and upper back velvety-black, shading to blackish-grey on the lower back and scapulars and to dark grey on the innermost secondaries; least wing-coverts and edge of wing white, shading to silver-grey on the median and to dove-grey on the greater coverts ; first and second primaries dark brown, with a long wedge-shaped white patch from base almost to the end of the first primary; second and third primaries dark grey, with the usual white wedges; remaining primaries silver-grey on the outer webs, darker on the inner.
Colours of soft parts. Iris dark brown; bill and feet vermilion, darker in winter.
Measurements. Wings 191 to 220 mm.; tail 69 to 75 mm.; tarsus 20 to 21 mm.; culmen 24 to 27 mm.
In Winter only differs from leucopareia in its smaller size.
Distribution. Temperate Asia and Europe, in Winter migrating south to all Western India and Ceylon and to Burma, China and nearly all the Malay islands. In India, although common all down the East coast, it is very rare elsewhere but has been found in Raipur in the Central Provinces, whilst Hole, Primrose and I all obtained specimens in Cachar and Sylhet.
Nidification. Very similar to that of the preceding bird. The eggs differ in being much smaller, very much darker and, nearly always, distinctly brown in general tone. Eighty eggs average 34.7 x 24.9 mm.: maxima 37.3 X 26.2 and 34.8 x 27.0 mm.; minima 29.4 x 22.7 mm.
This Tern commences to lay in the last week in April in Spain and in more Northern parts lays up to the end of June.
Habits. Much the same as those of our Indian Whiskered Tern.