186 BULLETIN 142, UNITED STATES NATIONAL MUSEUM 



Food. — Very little seems to have been published on the food of 

 the white-rumped sandpiper, but W. L. McAtee (1911) gives it 

 credit for eating some injurious insects and worms, such as grass- 

 hoppers, the clover-root curculio, which is injurious to clover, and 

 marine worms {Nereis), which prey on oysters. 



Stuart T. Danforth (1925) says that four collected in Porto Rico — 



had eaten 77.7 per cent of animal food and 22.3 per cent of vegetable matter. 

 Fifty per cent of the animal matter consisted of bloodworms, 25 per cent of 

 Planorbis snails, and 5 per cent of Corixa reticulata. The vegetable matter 

 consisted entirely of seeds, of which those of Compositae formed 33.3 per cent, 

 Sesban emerus 30 per cent, and Persicaria portoricensis 36.7 per cent. In addi- 

 tion to food, the stomachs contained mineral matter (coarse red sand) forming 

 32.5 per cent of the stomach contents. 



Behavior. — Lucien M. Turner, who has had abundant opportunity 

 to observe this species in Ungava, writes in his notes : 



The flight of these birds is remarkably firm and swift, generally in an 

 nndnlatory manner and swerving to the right or left often with the body 

 inclined to one side, the wing nearly perpendicular, alternately presenting the 

 upper and lower surface of the body. Just before alighting the wings are 

 raised until the tips nearly touch over the back and for a moment held 

 outstretched and then slowly folded. The bird is quite active while searching 

 for food and seldom remains more than a few seconds in a spot, where it 

 constantly picks here and there for the minute organisms which form its 

 food. During this time all is activity and quite in contrast to the interval 

 while the tide is high and the bird is on the high land resting and digesting 

 its food. Here it is more sleepy and less easily disturbed. The eyesight of 

 these sandpipers is certainly very acute, as they are able to detect the 

 presence of a person at a long distance and give a twittering, snipey note, other- 

 wise regardless of approaching danger. In all their doings the utmost harmony 

 seems to prevail. The only object of their lives seems to be to gather food. 

 No sooner does the water begin to ebb than a few of these birds will swish 

 over some point of land with merry twittering, eagerly scanning the bank 

 for the least appearance of mud now being exposed. By the time the tide has 

 half ebbed myriads of these birds are sweeping back and forth along the 

 river. As the water shallows over well known bars, and scarcely has the 

 water shoaled enough to permit the birds to alight without swimming, than 

 as many sandpipers as can collect on the place eagerly alight and begin 

 probing the ooze for food. The lowering water is followed by the thronging 

 birds to the last inch. 



The flowing tide begins and the birds retreat carefully seizing every object 

 of food that the rising water brings to the surface. Often they are so 

 eager in their search that many birds are crowded into the deeper water 

 and save themselves only by flight. This or that place is quickly covered 

 over by the water and again the birds collect into larger flocks which now 

 sway to the right or left, alternately, exposing their silvery white underparts 

 which gleam in the sunshine like a stream of silver. The gray or brown of 

 their backs relieving the color as the long stream of birds pass by. They 

 partially halt their fight and become a compact flock, whereupon they separate 

 into smaller flocks which, as the water gradually rises and covers their 

 feeding grounds, now betake themselves to the higher lands of the banks above. 

 Here, around the pools on the highlands, or among the grassy margins of 



