LIFE HISTORIES OF NORTH AMERICAN GULLS AND TERNS. 217 



the water, in much the same way as the smaller terns. Mr. Philip H. 

 Gosse (1847) thus describes the process: 



High above the water we discern a bird, the snowy whiteness of whose 

 plumage contrasts with tlie blue sky. He flies rapidly round and round in a 

 large circle, quickly tiapping his wings without intermission. Suddenly he 

 arrests his flight, flutters his wings in rapid vibration, as he looks downwards, 

 but in a moment proceeds as before. It was doubtless a fish near the surface, 

 but which disappeared before he could descend. Presently he again stops 

 short, flutters ; then bringing the elbow of the wings to a right angle, descends 

 perpendicularly, but with a singular turning of the body, so as to present now 

 the back, now the belly, alternately, to the observer ; not, however, by a rota- 

 tion, but irregularly, and as if by jerks. But his purpose is again frustrated ; 

 for on nearly reaching the surface he recovers himself with a graceful sweep 

 and remounts on flagging wing. Again he circles, and again, and again stops ; 

 at length, down he swoops, disappears with a splash, and in a moment breaks, 

 struggling, from the wave, and, as if to rise burdened with prey were difficult, 

 flags heavily near the surface, and circling slowly round, gradually regains his 

 former altitude. 



Audubon (1840) says: 



They alight on the banks of raccoon oysters, so abundant in the inlets, and 

 are seen in company with the semipalmated snipe and the American oyster- 

 catcher, searching for food like these birds, and devouring crabs and such 

 fishes as are confined in small shallow pools. These they catch with considerable 

 agility, in a manner not employed by any of our other terns. 



Mr. A. W. Anthony (1906) says that they feed on herring " swim- 

 ming in compact flocks near the surface," and " secure them by ap- 

 proaching the school from behind and flying near the surface of the 

 water, making repeated, quick dips into the school." They also eat 

 shrimps. 



Behavior. — The flight of the royal tern is much like that of the 

 common tern, but somewhat less bouyant, as might be expected in a 

 larger and heavier bird. On the wing it is lighter in appearance 

 than the Caspian tern, as it is more slender, and it has a longer and 

 more deeplj' forked tail, with less black in the outer end of the wing. 

 Audubon (1840) says: 



When traveling, these birds generally proceed in lines ; and it requires the 

 power of a strong gale to force them back, or even to impede their progress, 

 for they beat to windward with remarkable vigor, rising, falling, and tacking 

 to right and left, so as to .seize every possible opportunity of making their 

 way. In calm and pleasant weather they pass at a great height, with strong 

 unremitted flappings. 



Though webfooted and perfectly capable of swimming, these and 

 other terns seldom alight on the water and are very poor swimmers. 

 Their feet are rather small and weak, as they depend almost en- 

 tirely on their long wings for locomotion. 



The voice of the royal tern is not so loud and raucous as that of 

 the Caspian and is pitched on a higher key. The note most often 

 heard, when disturbed on its breeding grounds, is a loud penetrating 



