106 THE TERNS 



arms, to help them over the inequalities of the ground. One, which 

 tumbled into a small hole, put considerable pressure on its arms to 

 help itself out. In this habit they differ from the chicks of the black- 

 headed-gulls, which run with their wings closed unless hard pressed, 

 when they open them, moved thereto by what seems an instinctive 

 desire to take flight. The method of the little gulls is much better 

 adapted to escape through marram grass than that of the little terns, 

 whose outspread arms are a hindrance rather than a help. It is on 

 shingle or rough stony soil that the latter find their arms of use, a fact 

 noted already in the case of the Arctic-tern (p. 89). This points to 

 the probability that such ground is their natural nesting habitat. 



The chicks are fed by their parents on small fish, which are either 

 put in their beaks or dropped in front of them. When they are fledged, 

 they are fed in the air as well as on the ground. 



The parent birds differ from the other British terns in their 

 method of fishing, in that it is their usual habit to dive right under the 

 water, and remain under an appreciable time some two to three 

 seconds. Like the others, they hover, before diving, over the water. 

 This they do at various heights, from twenty to sixty feet more or less, 

 their beaks being usually directed straight downward. When they 

 have marked their fish, they drop suddenly in an oblique direction, 

 using their wings, which remain partly open to direct their course. 

 They appear to close them, or nearly so, immediately before entering 

 the water, which they do with a splash. Like the other terns, they 

 also pick food off the surface of the water, after the manner of gulls, 

 that is, without alighting. 1 



The Sandwich-tern has not appeared to me as aggressive in de- 

 fence of its eggs and young as the common and Arctic, though, like 

 them, it will swoop down upon intruders. Naumann states that it 

 attacks vigorously, and strikes them with the wings. If the Sandwich 

 does strike with the wings, it differs in this respect from the common 

 and Arctic, who, as already noted, strike with the point of the beak. I 



1 See p. 90. 



