LIFE HISTORIES OF NORTH AMERICAN GULLS AND TERNS. 257 



weather was clear, with a light southwest wind, On the 10th, at sunrise, the 

 Wilson's and roseate terns were rising in very large numbers from the northern- 

 middle part of Muskeget proper, the weather, being clear, with a strong south- 

 west wind. On the 11th they continued to increase. There was a strong south- 

 west gale during the night, dying out in the forenoon. 



Courtship. — During the last week in May, while the countless 

 hordes of terns are gathering on these breeding grounds, the roseate 

 terns may be seen flying about in pairs or chasing each other in the 

 air, with their long slender tail feathers streaming behind; or, in 

 the dense flocks, resting and sunning themselves on the beach, their 

 simple courtship may be seen. Both birds show their interest in each 

 other by stretching their necks upward and strutting about with 

 drooping wings and elevated tails ; or standing side by side they 

 exchange greetings. Finally the accepted suitor mounts his mate 

 arid stands squarely upon her back for a long time, with frequent 

 interlocking Of bills. The nuptial caress is most deliberate; and 

 after it is over they stand close together, billing and cooing and 

 preening each other's plumage. 



Nesting. — The finest breeding colonies of roseate terns, so far as I 

 know, are at Chatham and on Muskeget Island, Massachusetts. The 

 most important of these is on Muskeget Island, a low sandy island 

 lying between Nantucket and Marthas Vineyard, which has been 

 more fully described under the common tern. On my various visits 

 to this island I have always found roseate terns nesting here abund- 

 antly, although they have always been far outnumbered by the com- 

 mon tern. The nests of the common tern were scattered in various 

 situations all over the island, arid occasionally a few nests of roseate 

 terns were found among them, but the main stronghold of the 

 roseate terns was on the southern extremity of the island, separated 

 from the main island by a long, narrow beach; here, except for a 

 few scattering pairs of common terns, the whole population was 

 made up of roseates. We determined this fact to our own satisfac- 

 tion by trapping nine of the birds on their nests in snares made of 

 very fine steel wire. This usually did not injure the birds at all, as 

 we soon released them. The nests were closely congregated on the 

 highest part of the point, particularly along the crest of a little 

 ridge which rose abruptly from the beach. They were mostly well 

 concealed, in the thick growth of tall beach grass (AmmophUa 

 arundinacea) , which grew luxuriantly at this end of the island. 

 Some of the nests were hidden among the poison-ivy vines (Rhus 

 rddicans) , or under the shade of herbaceous plants. Often the nests 

 were arched over with the tall grass, having pathways leading to 

 them, and almost always they were more or less under cover, in 

 marked contrast to the nests of the common tern, which were always 

 in open places. In many cases the eggs were laid on the bare sand, 



