LIFE HISTORIES OF NORTH AMERICAN GULLS AND TERNS. 307 



they were able to eat food deposited near them, as the adult often 

 disgorges the food on the rim of tlie nest. They also soon learn to 

 keep the nest clean by forcing their fecal matter far out over the 

 rim of the nest. At just what age they learn to fly he does not state. 



Plumages. — The downy young seems to have two color phases — 

 a dusky phase and a white phase. The only specimen that I have 

 seen is sparingly covered with short, dirty white down, tinged with 

 buffy, Avith signs of a few black feathers coming in on the center of 

 the back, the wings, and the crown. Two of the specimens shown in 

 Professor AVatson's (1908) plate seem to be quite dusky. At an age 

 of 18 days the young bird seems to be about half fledged, and at .30 

 days practically fully feathered. This juvenal plumage much re- 

 sembles that of the adult ; it is " bone brown " above and " fuscous " 

 below ; the feathers of the back, scapulars, and wing-coverts are 

 tipped with " Avood brown," which fades later to buffy white ; the 

 pale gray cap is acquired and the throat is largely grayish white. 



Yarreil (1871) says: 



In birds which are not fully matiiro the l)lack lorsil streaks are less de- 

 fined ; tlie j:;ray of the forehead and throat is less pronounced, and the gen- 

 eral tint is browner. Birds of the first year have very little white on the 

 forehead : the mantle and winj? coverts are of a lighter brown, the secondaries 

 and tail feathers showing slight bars of umber-brown near the tips; under- 

 parts pale brown. 



As to subsequent molts we have very little data, but there seems 

 to be no conspicuous seasonal change, except on the crown. In 

 winter this is nearly as brown as the back, with only a narroAv white 

 supraloral line. The material examined seems to indicate a com- 

 plete postnuptial molt and probably a complete prenuptial molt. 



Food. — In regard to the feeding habits of these terns, Professor 

 Watson (1908) says: 



In a locality where marine forms are so abundant as in this favored Gulf 

 region, the terns collect their food with little difliculty. They feed upon small 

 fish of different kinds, which are present in great al)undance. Examination 

 of the stomach contents of both young noddies and sooties showed the presence 

 of representatives of the two fanulies of fish Carangidae and Clupeidae. 



To my great surprise I found that the birds never swim nor dive. As a 

 matter of fnct, they never touch the water except when drinking or bathing. 

 The bird drinks the seawater as it skim.s the surface of the water with open 

 beak. Bathing they perform in much the same way, never coming to a stop 

 in the water nor completely inmiersing the body; usually the breast and head 

 are the only parts dipped into the water. 



The birds fish by following schools of minnows which are being attacked 

 by larger fish. The minnow, in its efforts to escape, jumps out of the water 

 and skims the surface for a short distance. The terns pick off these minnows 

 as they hop up above and over the surface of the water. The rapidity and 

 accin-acy of visual-motor adjustment in this reaction is wonderful. 



The birds feed singly or in groups; usually in groups. The group may be 

 composed of both noddies and sooties and may contain sometimes as many as 



