3o8 THE NESrS AND EGGS OF 



Family LARID/E. Genus Hydrochelidon. 



Sub-family S TERMING. 



BLACK TERN. 



Hydrochelidon nigra {Liimceus). 



(British : Formerly bred ; regular spring and autumn coasting 

 migrant.) 



Single Brooded. Laying season, latter end of May, and in 



June. 



Breeding area : South-western Palaearctic region. 

 The typical form of the Black Tern breeds as far north 

 as the province of Esthonia south of the Gulf of Finland, 

 thence southwards through the Baltic Provinces, Prussia, 

 Southern Scandinavia, Denmark, Holland, France, and 

 the Spanish peninsula, and eastwards throughout Central 

 and Southern Europe in all suitable districts, to the 

 Caspian. In Asia it breeds in South-western Siberia 

 and Turkestan, to as far east as the Altai Mountains. 

 South of the Mediterranean it breeds throughout North 

 Africa with the exception of Egypt. The Nearctic 

 form of this species is known as Hydrochelidon nigra 

 stirinamensis. 



Breeding habits : The Black Tern reaches its 

 accustomed breeding places in May. It is a gregarious 

 bird, nesting in colonies of varying size, and sometimes 

 in company with the following species. There can be 

 little doubt that it pairs for life. The favourite breeding 

 haunts are marshes and weed-grown shallow lakes and 

 pools, either near the sea on lagoons, or in inland 

 localities. The nests are made either amongst the reeds 

 or eqnisetums at some distance from the bank in shallow 

 water, or amongst the hassocks of sedge and other coarse 

 vegetation in the marshes. They are large and bulky 



