TERNS 



(63) Qelochelidon nilotica 



(Linn.) (Gr., laughter, a swallow; of the 

 River Nile). 



GULL-BILLED TERN: MARSH 

 TERN. Bill black, rather short and 

 stout. Feet black. Ad. in summer 

 — Crown and nape black ; mantle 

 pale pearl; outer webs of pritimries 

 silvery, inner web black at tip and 

 along shaft line; under parts and tail 

 pure white; tail very slightly forked. 

 In winter — Crown white ; spot in front 

 of eye dusky and more or less dusky 

 on the nape. L., 14.50; Ex., 36.00; 

 W., 12.00; T., S-S°', B., 1.40, its 

 height at base .45. Eggs — Three 

 or four, creamy-white with blotches 

 of brown and gray, i.Sox 1.30; laid 

 on broken flags in marshes. 



Range — Breeds along the Gulf 

 coast and along the Atlantic coast 

 to Virginia. Strays rarely to Maine. 



TERNS, Sub-family Sterninae, are birds of generally 

 more slender form than gulls. Their bills are relatively 

 longer, slenderer and sharply pointed; the tails are, in all 

 species, more or less deeply forked; and the webbed feet and 

 legs are comparatively small and weak. 



They are very graceful and far more active in flight than 

 gulls, and at such times the head and bill are usually carried 

 p>ointing downward. Although they can swim, they very 

 rarely do so. Their food consists chiefly of insects or small 

 fish; the latter they secure by plunging or hovering just 

 over the surface and dipping the head. 



GULL-BILLED TERNS inhabit nearly all temperate 

 parts of the world, but are quite local in their distribution. 

 In North America they are found regularly only on the 

 South Atlantic and Gulf coasts. They can easily be dis- 

 tinguished from any gulls by the ternUke or swallowlike form 

 and flight, and from any others of the terns by the compara- 

 tively short, heavy, black bills and nearly square-ended tails. 



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