RISSA.
Hind toe rudimentary; breed in colonies on sea cliffs ; nest of seaweed and grass ; eggs 3, variable, ground colour greenish white, pale ochreous or light olivaceous marked with dark brown and purplish grey.
Rissa tridactyla tridactyla (L.). KITTIWAKE. Fr. Mouette tridactyle ; Ger. Dreizehenmowe ; Ital. Gabbiano tridattilo ; Swed. Tretaig Masc.
summer. Head, neck, tail coverts, tail, and underparts white ; back, upper wing coverts and scapulars light blue grey, last with white tips ; primaries and secondaries light grey, outer web of 1st primary and tips of outer primaries black, tips of inner primaries and secondaries white. Bill yellow with green tinge. Gape and eye-rim red. Iris brown. Legs and feet dark reddish brown. In winter, occiput, nape and sides of neck are slaty grey.
Wing 303-325. Tarsus 31-34. Bill 31-35. Young: nape and hind neck white, tipped black, forming a half collar, behind ear coverts a dark spot, scapulars and inner wing coverts brown, subterminal black band on tail, bill black.
Breeds.—Brittany Coast (rare), British Isles, Faroes, Iceland, Spitzbergen, Franz Joseph Land, and on Norwegian Coasts and _ Murman Coast of N. Russia ; also in N. Asia, Greenland, and E. Coast N. America. Some move south in autumn and winter ; occurs then in Mediterranean, Canaries, Azores, NV. Coast Africa to Senegal and Cape de Verde, and in America to Great Lakes, Bermuda, and N. United States. Abundant in N. Atlantic after the breeding season.