l56 BULLETIN 14 6^ UNITED STATES NATIONAL MUSEUM 



the large, flat, marshy islands. These are mud islands raised but a 

 few feet above high water and some of them are partially flooded 

 during spring tides ; they are mainly covered with salt-marsh grasses, 

 intersected by tidal creeks and dotted with small pond holes or bare 

 muddy splashes. The plover alighted on the bare spaces or in the 

 short grass, where the large flocks seen in the distance seemed to 

 whiten the ground. These large flocks, with sentinels always alert, 

 were utterably unapproachable; and even the small flocks and single 

 birds were as shy as ever. At low tide they resorted to the extensive 

 mud flats to feed, though they doubtless fed on the meadows also. 



On Cape Cod they frequent the same localities as in the fall; my 

 earliest date is April 19 and my latest date for adult birds is June 

 29. The spring flights here and in New Jersey are made up mainly 

 of adult birds, mostly in full plumage, but many are mottled and 

 there are always some " pale bellies," or young birds. 



The black-bellied plover is an abundant spring migrant up the Mis- 

 sissippi Valley and through central Canada. We saw it in Saskatch- 

 ewan during the last week in May and first week in June. C. G. Har- 

 old tells me that it is abundant around the prairie lakes and sloughs 

 in Manitoba. Prof. William Rowan (1926) calls it abundant in 

 Manitoba ; his notes mention a flock estimated at about 3,000 seen on 

 May 23, 1925, at Beaverhill Lake. He says: 



At our lake it is one of the later arrivals in tlie spring, seldom appearing 

 before the middle of May. It stays generally in some numbers till the end of 

 the month and may linger till the second week of June. Flocks are usually 

 small, anything up to 30, except when the birds are ready to start on the next 

 lap north, when they may aggregate many hundreds if not thousands. On May 

 23, 1925, we estimated the ground covered by *a single flock of grey plovers, 

 knots, and a sprinkling of goldens at about one and a half acr'es.. They were 

 not scattered, but neither were they closely packed. The grays made up about 

 75 per cent of the whole. The sitting flock looked like a large patch of snow. 



S. F. Rathbun has sent me the following notes from Washington 

 which illustrates the abundance of this species on the Pacific coast: 



May 12, 1927. This morning was a dark one with a steady drizzling rain 

 and light wind following the storm of the preceding two days. On reaching a 

 very wide expanse of grassy salt meadows bordering the bay we found them 

 dotted nearly everywhere with many of the smaller sandpipers and black-bellied 

 plover, the birds being in small and large flocks and mostly grouped around the 

 many shallow pools with which the meadows were flecked. It was one of the 

 finest sights we have ever seen where shore-birds were concerned. The beautiful 

 black-bellied plover in fuU nuptial dress were scattered over a wide area, rarely 

 as single birds, but ordinarily a number in company and not infrequently in 

 flocks of considerable size. One such flock consisted of 50 individuals, shortly 

 after being joined by another of some 30 birds, the combination of so many large 

 black-breasted birds making a striking sight. When first alighting the birds 

 would stand motionless, following which they would then move slowly about, 

 although at times individuals might take wing, make several turns in the air 



