WESTERN SANDPIPER 261 



with it, as such flight notes sometimes are. Its closest resemblance with a 

 note of the semipalmated is to the senip sometimes heard from that bird when 

 flushing. 



Some of the calls of the western are apparently indistinguishable from those 

 of the semipalmated sandpiper, but as studied on the northwest coast of 

 Florida, where it greatly outnumbered the other form, more seemed different. 

 Birds took wing with a sirp, or at another time a chir-ir-ip, which heard also 

 in a medley of variations from a flock already on the wing, suggesting the 

 notes of the horned lark, may be more or less analogous with the short flocking 

 note of the semipalmated sandpiper. 



Field marks. — It is most difficult and often impossible to dis- 

 tinguish between the western and the semipalmated sandpipers in 

 life; and I have experienced difficulty in distinguishing between 

 them even in the hand. The western has a longer bill, and I believe 

 that the bill measurements of corresponding sexes do not overlap, 

 though they approach very closely; but the longest-billed female 

 semipalmated may have a longer bill than the shortest-billed male 

 western. In spring and summer plumages the western shows much 

 more rufous in the upper parts and is more conspicuously and more 

 heavily streaked on the breast, but in winter plumage the two species 

 are very much alike. Mr. Nichols has given me a few characters 

 by which this species can be recognized even in winter; he calls it 

 " a somewhat larger, rangier, paler, grayer bird " than the semi- 

 palmated ; it also has " better developed white stripes over the eyes 

 which meet more broadly on the forehead, the top of the head is 

 not so dark, its dark auricular area is not so prominent, the mark- 

 ings on the top, and particularly on the sides, of the head and neck 

 are finer. 



As to the bills, he says : 



There U a subtle difference in their bills, however, which I have frequently 

 noticed in life and once or twice checked by taking specimens. The bill of a 

 long-billed semipalmated sandpiper is quite straight and becomes slender 

 toward the end; that of a short-billed western is not so slender toward the 

 end and with just an appreciable downward bend before its tip. In long- 

 billed individuals of the western sandpiper the bill becomes slender toward 

 the end and frequently has a decided drop at the tip. Such birds are un- 

 mistakably different to anyone thoroughly familiar with the semipalmated 

 sandpiper. 



Fall. — Like many other waders, these little sandpipers begin to 

 move off their breeding grounds at a very early date. As early as 

 June 21, 1914, F. S. Hersey saw western sandpipers flocking at the 

 mouth of the Yukon River, Alaska. Some of the flocks contained 

 from 40 to 60 birds. The larger flocks were all of this species, 

 but the smaller flocks often contained one long-billed dowitcher. 



Doctor Nelson (1887) says, of its fall wanderings: 



Early in July the young are on the wing and begin to gather in flocks toward 

 the 1st of August. The last of these birds are seen on the coast of Norton 



54267—27 18 



