280 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



It was curious to observe their actions whenever a large party landed on the 

 island. All those not engaged in incubation would immediately rise in the air 

 and scream aloud ; those on the ground would then join them as quickly as 

 they could, and the whole forming a vast mass, with a broad extei;ded front, 

 would as it were charge us, pass over for 50 yards or so, then suddenly wheel 

 round and again renew their attack. This they would repeat six or eight times 

 in succession. When the sailors, at our desire, all shouted as loud as they 

 could, the phalanx would for an instant become perfectly silent, as if to gather 

 our meaning ; but the next moment, like a huge wave breaking on the beach, it 

 would rush forward with deafening noise. 



Spring. — A description of this island is given in the life history of 

 the noddy. Dr. Joseph Thompson (1903) says that sooty terns ar- 

 rive about a week after the coming of the noddies ; they " arrive in 

 larger flocks and they all seem to reach the breeding place within 

 about four days. Within a week of the arrival of the first one their 

 eggs are to be found." 



Courtship. — Audubon (1840) witnessed the courtship of this spe- 

 cies, of which he writes : 



The male birds frequently threw their heads over their backs as it were, in 

 the manner of several species of gulls ; they also swelled out their throats, 

 walked round the females, and ended by uttering a soft pufRng sound as they 

 caressed tliem. Then the pair for a moment or two walked round each other, 

 and at length rose on wing and soon disappeared. 



Nesting. — From Prof. John B. Watson's (1908) careful observa- 

 tions of this species and the noddy, made in this colony, we have 

 learned much regarding their habits and characteristics. Some of 

 this information I shall attempt to give in concise form or in exact 

 quotations from his excellent paper, to which I would refer the reader 

 for details. Regarding the nest-building activities he says : 



The building of the sooty nest is quickly accomplished. The obtaining of a 

 nest site is the difficult part of the reaction. As has been said, the sooties 

 build their nests veiy near one another. For this reason it is extremely difficult 

 to make complete observations. My observations began late one afternoon, 

 before any eggs had been laid. Hundreds of the birds were grouped together, 

 incessantly fighting and screaming. It quickly became apparent that most of 

 them had chosen a nest site and were defending it against all late comers. 

 Both male and female were present. Each pair in this particular locality de- 

 fended a circular territory, roughly 14 inches to 2 feet in diameter. Other 

 biras in wandering around would stumble into this sacred territory and a fight 

 would ensue. The fights would often lead to encroachments upon the territory 

 of still other birds. The number of those fighting would thus be constantly 

 increased. I have seen as many as 14 sooties thus engaging in a fight. Birds 

 10 to 15 feet away would rush into the fight and the noise and confusion beg- 

 gared description. Sometimes as many as 10 or 15 such fighting groups could 

 be observed in the area of 1,000 square feet. Quiet would momentarily ensue 

 and then be broken by another series of fights. During the choice of the nest- 

 ing site the fights continue day and night, with only intermittent periods of 

 QUlet. 



