GULLS AND TERNS. 39 



Owing to the great diversity of its haunts the 

 Black-headed Gull is almost omnivorous in its diet. 

 Inland it feeds on grubs especially wire- worms- 

 insects, worms, fresh -water fish, and newly sown 

 grain, as I have often ascertained by dissection ; on 

 the sea coast it subsists on fish, crustaceans, and 

 various odds and ends obtained about harbours or 

 vessels. It seeks its food both whilst swimming 

 about the water, fluttering above it, or when 

 walking on the shore. This Gull is much more 

 Tern-like in its habits than the larger species we 

 have already dealt with. Of its services to the 

 agriculturist there can be no question ; it is just as 

 useful on the land as the Rook, without that bird's 

 few little pilfering ways. 



The Black-headed Gull is an inland breeding 

 species, and resorts to marshes, wet moors, and 

 meres, at varying distances from the sea. Some- 

 times these breeding-places are in fairly well- 

 timbered districts, and often surrounded by trees 

 and bushes. This Gull, too, is remarkably 

 gregarious during the breeding season, and some 

 of its colonies are very extensive, consisting of 

 many thousands of pairs. The "gulleries" are 

 visited for nesting purposes in March or April, and 

 as the birds return to the same spots year after 

 year, they probably pair for life. Nesting begins 

 in April. Most of the nests are made upon the 

 ground in rush tufts, in hassocks of coarse grass 

 and sedge, amongst reeds in shallow water, on 



