252 BULLETIN" 142., UNITED STATES NATIONAL MUSEUM 



July 10 to October 30 are the usual dates, but few are seen after 

 September 20. The adults come first, but after the middle of 

 August the young appear, to be distinguished by their nearly white 

 breasts washed with a smoky tint, and by their more unsuspecting 

 ways. 



The extraordinary abundance of this species at certain times on 

 migration is well illustrated by what Stuart T. Danforth (1925) says 

 of it in Porto Rico. He writes: 



The seinipalinated sandpiper is by far the most abundant shore bird at 

 Cartagena Lagoon, though it occurs only as a fall migrant. I have records 

 from August 13 to October 20, 1924. During the latter part of August they 

 are present in almost unbelievable numbers. I hardly dare estimate their 

 numbers, but on August 26, when they were at the height of their abundance, 

 I am sure that 100,000 would have been a low estimate of their numbers. 

 They simply swarmed over the mud flats. On this date, although I was trying 

 to avoid shooting them, I got 16 while shooting other birds. They were so 

 abundant that stray shots could not help killing numbers of them. On other 

 days many were also unintentionally shot in the same manner. In fact, all 

 but 4 of the 36 that I collected were shot in this way. This species pre- 

 fers the mud flats, but when they were so excessively abundant some were 

 forced to feed in the sedge and grass associations, and when the fall rains 

 came a little later practically all of them were forced to the sedges and 

 grasses and even to the cane fields. But within a few days after this most of 

 them left for parts unknown. 



DISTRIBUTION 



Range. — North America, South America, the West Indies, and 

 northeastern Siberia ; accidental in Europe. 



Breeding range. — The semipalmated sandpiper breeds north to 

 the northeastern coast of Siberia (Plover Bay) ; Alaska (Point 

 Hope, Point Barrow, Barter Island, Camden Bay, and Demarcation 

 Point) ; Yukon (probably Herschel Island) ; Mackenzie (Franklin 

 Bay), Victoria Land; northern Keewatin (Cape Fullerton) ; Labra- 

 dor (Okak) ; and Newfoundland. East to Labrador (Okak) . South 

 to Labrador (Okak); Newfoundland; northern Quebec (Fort 

 George) ; southern Keewatin (Severn River) ; probably eastern Man- 

 itoba (York Factory and Fort Churchill) ; Mackenzie (Fort Ander- 

 son) ; and Alaska (Pastolik). West to Alaska (Pastolik, Hooper 

 Bay, St, Michael, probably Nome, Port Clarence, Kowak River, 

 probably Cape Blossom, and Point Hope) ; and northeastern Siberia 

 (Plover Bay). 



Winter range. — North to Sonora (Hermosillo) ; Texas (Fort 

 Brown, Corpus Christi, and Refugio County) ; Louisiana (State 

 Game Preserve, Marsh Island, False River, and Hog Bayou) ; and 

 South Carolina (Bulls Point). East to South Carolina (Bulls Point, 

 Sea Islands, Frogmore, and Port Royal) ; Georgia (Chatham County, 

 JBlackbeard Island, Darien, and St. Marys) ; Florida (Mosquito Inlet 



