22 GAME, AQUATIC, AND RAPACIOUS BIRDS. 



insects, so that our fields were entirely freed from them. The settlers at Salt Lake 

 regarded the advent of the birds as a heaven-sent miracle. * * * I have been 

 along the ditches in the morning and have seen lumps of these crickets vomited up 

 by these gulls, so that they could again begin killing. 



These " lumps of crickets" were undoubtedly " pellets" of the indi- 

 gestible parts habitually disgorged by the birds. At the time of 

 the Nevada mouse plague in Humboldt Valley in 1907, gulls, as 

 well as hawks and owls, were noted feasting on the destructive 

 rodents. F. E. L. B. 



TERNS. 



Like the gulls, terns are usually associated in the mind with the 

 seacoast, but at least six species breed in the interior of the continent. 

 The terns are expert in flight, and so trim and graceful in appearance 

 that they have received the name sea swallows. They breed in 

 colonies, usually nesting on low islands. This leads to the destruc- 

 tion of large numbers of eggs and young by high tides. Formerly 

 terns were slaughtered for millinery purposes to such an extent that 

 some species have been almost extirpated. 



Persons engaged in the plumage business have made the not 

 disinterested charge that terns devour large numbers of food fishes 

 and hence should be destroyed. In order to ascertain the truth of 

 the matter the Biological Survey has made a thorough examination 

 of the question. Too few stomachs of the Caspian, roseate, and 

 arctic terns have been examined to form a basis for satisfactory con- 

 clusions, but a fair number of stomachs of five other species were 

 available the royal tern, Forster's tern, common tern, least tern, 

 and black tern. 



Royal tern (Sterna maxima). Twenty-four stomachs were ex- 

 amined. They contained 3 per cent of Crustacea and 97 per cent of 

 fish. The fishes were yellow perch (Perca flavescens), 4 per cent, 

 taken in North Carolina in July; bluefish (Pomatomus saltatrix) , 8 

 per cent, taken in Florida in March; menhaden (Brevoortia tyrannus), 

 65 per cent, taken in Georgia in November and December, Alabama 

 in October, and Florida in February, August, October, November, 

 and December; and unidentified fishes, 20 per cent. 



Thus it is probable that not more than 16 per cent of the normal 

 food consists of fishes eaten by man. The feeding upon menhaden, 

 tons of which are made into fertilizer, is insignificant economically. 



Forster's tern (Sterna forsteri). The food of 34 specimens of 

 this species consisted of Crustacea, 2 per cent, and fish, 98 per cent. 

 The largest item of finny food was menhaden (Brevoortia tyrannus), 

 28.2 per cent, found in stomachs taken in South Carolina, Georgia, 

 and Florida in November, December, and January, respectively. 

 Silvery anchovies (StolepTiorus) (not the anchovies of commerce), 



497 



