LIFE HISTORIES OF NORTH AMERICAN GULIiS AND TERNS. 289 



Plu77iages. — The downy young bridled tern is gray, to match the 

 rocks on which it is born. The color varies from very light gray to 

 dark gray or drab-graj', and it is usually tinged with buff; the 

 under parts are grayish white and the throat is dark gray ; the upper 

 parts are more or less mottled with dark brown. The young bird, 

 in the juvenal plumage, has the forehead and the entire under parts 

 pure Avhite. The crown and hind neck is " light gull gra}''," lightly 

 streaked on the crown and heavily streaked on the cervix with black. 

 Ihe feathers of the back, lesser wing-coverts, or scapulars, are edged 

 with pale buff, which fades or wears away during the fall and winter, 

 leaving the back " gull gray " and somewhat mottled. The sequence 

 of plumages to maturity, so far as we can tell from the limited 

 material available, is apparently similar to that of the other small 

 species of the genus Sterna. The same is probably true of the molts 

 and plumages of the adult. The adult in winter may be distin- 

 guished from the young of the year by having no buffy edgings on 

 the upper j^arts, but the fresh feathers of the back are broadly tipped 

 with very " pale gull gray," or whitish ; and the head is more dis- 

 tinctly marked with black and white, though in a similar pattern to 

 that of the young bird. 



Food. — Dr. Alexander Wetmore (1916) says of the food of the 

 bridled tern : 



Of five stomachs examined one was entirely empty. Fish remains were pres- 

 ent in all the other stomachs, and amounted to 70 per cent. One species was 

 identified as a filefish (Alutera, species). Mollusks (25 per cent) were repre- 

 sented by a gastropod and a cephalopod (Spirula awitralis), the latter one of 

 the few of that order bearing a shell that exist to-day. Miscellaneous matter (5 

 per cent) consisted of a moth and a small echinoderm. Fish and marine mol- 

 lusks form the large bulk of the food, and under present conditions the birds 

 are to be considered harmless, as the fish eaten are not of economic importance. 



In its feeding habits, flight, vocal performances, and general be- 

 havior it is apparently similar to the sooty tern. I can not find that 

 anyone has noted any special peculiarities of the bridled tern. On its 

 breeding ground it is often intimately associated with other tropical 

 terns in large colonies, also with boobies and other water birds, with 

 all of whom it seems to live in perfect harmony. At the close of the 

 breeding season, in August or September, it leaves with the others 

 and wanders about over adjacent seas and coasts during the winter. 



DISTRIBUTION. 



Breeding range. — The American form breeds in the Bahamas 

 (Acklin, Kleuthera, and Berry Islands, Atwoods, Samana, French, 

 and Gauldings Keys, etc.). Southward throughout the West Indies 

 (Dominica, Jamaica, Porto Eico, St. Thomas, etc.) to Venezuela 

 (Arnba Island). Westward throughout the Caribbean Sea to 



