770 A FRA .TICAL HANDBOOK OF BRITISH BIRDS. 



at varying heights, but also on low -lying coasts. Nest. — Large, 

 built chiefly of moss and grass. Eggs. — 2-3 in number, like those 

 of Glaucous Gull, but decidedly smaller : ground-colour stone or 

 clay, with umber spots and blotches. Average of 61 eggs, 68.64 X 

 48.26. Max. : 75.8x49.7 and 72.2x51.3. Min. : 62.5x49.6 and 

 65.7x44.7 mm. Breeding -season. — From end May to early July. 

 Incubation. — No details available. Single brooded. 



Food. — Small fish of northern species (Salmo arcticus, Clupea 

 sprattus, young herrings, etc.), also stranded and dead fish and fish- 

 refuse, as well as carrion of all kinds : Crustacea, mollusca ; and in 

 winter largely on vegetable matter (grain, etc.). Young said to 

 feed on berries of Empetrum nigrum (Hagerup). 



Distribution. — British Isles. — Winter- visitor, sometimes until 

 April and May. Much same as Glaucous but decidedly scarcer. 

 Many Cornwall and Devon winters 1872-3 and 1874-5. 



Distribution. — Abroad. — Breeds apparently Jan May en, certainly 

 Greenland and arctic America to Victoria Land and Boothia 

 Peninsula. [According to Smirnow, 1901, Novaya Zemlia, but this 

 requires confirmation.] In winter south to Iceland, Scandinavia, 

 Faeroes, Bay of Biscay (rare), casual Baltic, Italy, Madeira ; in 

 America casually to Great Lakes, to Long Island, r accidentally 

 Nebraska, Maryland, California. 



Genus RISSA Steph. 



Rissa Stephens, Shaw's Gen. Zool., xiii, 1, p. 180 (1826 — Monotype : 

 R. brunnichii=tridactyla). 



Tarsus shorter than middle toe and claw. Hind toe rudi- 

 mentary, as a rule without claw, but sometimes tiny claw present. 

 Middle rectrices very slightly shorter, thus tail not absolutely 

 square. Two species in northern seas. 



RISSA TRIDACTYLA 



459. Rissa tridactyla tridactyla (L.)— THE KITTIWAKE GULL. 



Lartjs tridactylus Linnaeus, Syst. Nat., ed. x, i. p. 136 (1758 — 1ST. 



Europe. Restricted typical locality : Great Britain). 



Rissa tridactyla (Linnaeus), Yarrell, in, p. 650 ; Saunders, p. 683. 



Description. — Adult male and female. Winter. — Fore-head white ; 

 crown and nape dark blue-grey with some white showing, feathers 

 having white bases and inclining to streaky appearance on crown ; 

 lower-neck and upper-mantle white clouded grey, feathers being 

 tipped dark grey ; mantle, back, upper -rump and scapulars dark 

 blue-grey, long scapulars tipped white ; lower-rump, upper tail- 

 coverts and tail white ; anterior corner of eye streaked blackish- 

 grey ; posterior ear-coverts and sides of neck dark blue-grey ; rest 

 of under-parts white but under wing-coverts along edge of wing 

 tipped grey ; primaries : 2nd (outer) with long tip and outer web 



