THE BLACK-NECKED GREBE. 461 



and white on inner primaries, also in summer by black fore-neck, 

 in winter and juvenile by brown of crown extending below eye and 

 on ear-coverts ; considerably larger than Little Grebe and smaller 

 than Red-necked. 



Field -characters. — In breeding plumage black neck and tuft of 

 golden feathers radiating from eye across black cheek distinguish 

 it from Slavonian Grebe, to which it approximates in size. Closely 

 resembles that species {q.v.) in winter, but dark colour of crown 

 extends below eye ; an infallible distinction is the slender tip-tilted 

 bill. Call-note a soft " pee-ep." In breeding-season utters a rippling 

 trill, " bidder, vidder, vidder, vidder " ; alarm-note, " whit, whit." 

 Hunger cry of young closely resembles that of Great Crested and 

 Little Grebes. 



Breeding-habits. — Haunts lagoons, reedy ponds and reservoirs, 

 and where plentiful breeds in colonies. Nest. — Usual heap of wet 

 water -weeds and vegetable matter built up in water and sheltered 

 by reeds and water-plants. Eggs. — Usually 4, occasionally 3, 5 or 

 even 6, while 7 and 8 are on record from Germany, white when 

 fresh, with chalky surface which absorbs nest -stains rapidly. 

 Average of 100 eggs, 43.9x30.2. Max.: 48.5x32 and 40x34. 

 Min. : 39x27.1 mm. Breeding -season. — From end April onward 

 but usually in May or June. Incubation. — By both sexes. Period 

 about 20 days (Pike). Probably single brooded, but not positively 

 known. 



Food. — Fish only taken to small extent, and main food insects ; 

 coleoptera {Dytiscus and larva, Noterus, Donacia, Badister bipunc- 

 tatus, Phylangibbus, etc.) ; hymenoptera (ants) ; phryganeidse 

 (caddis -worms) and Notonecta. Mollusca, Crustacea {Mysis vulgaris), 

 and considerable quantities of feathers also recorded from stomachs. 

 Young fed on small fish in Herts (Oldham). 



Distribution. — British Isles. — Resident and winter -visitor, arriv- 

 ing Sept .-Nov. Known to have bred regularly in Wales since 1904, 

 and in west Ireland since 1915 (in a second locality 1918), while a 

 few pairs have also bred at Tring Reservoirs (Herts.) since 1918, 

 and has nested on another reservoir in Bucks. ; also some evidence 

 of breeding on occasions in Norfolk, Oxon., and Perth. Otherwise 

 irregular visitor, chiefly autumn to spring, but sometimes summer 

 and most frequently northern half of east coast England, and 

 Merioneth. Elsewhere very uncommon, while in north-west 

 England and west and north Scotland and Orkneys rare vagrant 

 and not known O. Hebrides or Shetlands. In Ireland very scarce. 

 Occasional inland waters. 



Distribution. — Abroad. — From Denmark and Baltic countries 

 southward throughout Europe and through temperate Asia to 

 China and Japan. Straggler to Madeira, Canaries and Azores. 

 Replaced by closely-allied forms in North America, and Africa 

 south of Sahara. 



