(60,000 in Alaska) in the early 1970's (Bellrose 1976). 



Winter The U.S. wintering population was believed to be about 123,000 

 birds (the 90,000 breeding birds, plus juveniles and subadults) during the ear- 

 ly 1970's. About 55,000 of these wintered in the east, of which 40,000 were in 

 Chesapeake Bay (Bellrose 1976). The 1975 winter waterfowl survey (Goldsberry 

 et al. 1980) reported about 120,900 Whistling Swans. About 45% of these were 

 in the Pacific Flyway , and almost all the rest were found in the Atlantic Fly- 

 way. The great preponderance of those wintering in the southeastern states were 

 found in North Carolina, which harbored about one third of the population win- 

 tering along the Atlantic seaboard. Only California (ca. 46,000) and Maryland 

 (36,400) had larger wintering populations. 



Migration The Athabasca Delta is a major fall staging area for swans from 

 western and northern Alaska and from much of the Canadian breeding range. From 

 there, many birds move southwest through Montana and Utah to wintering areas in 

 the west. Most of the birds wintering on the Atlantic coast also gather in the 

 Athabasca Delta but fly east-southeast through Manitoba, North Dakota, and the 

 Great Lakes States to the Chesapeake Bay area (Bellrose 1976). 



In Chesapeake Bay, fall migrants continue to arrive during December and 

 reach peak numbers in January (Bellrose 1976). The spring departure for Whis- 

 tling Swans wintering in the east begins in early or mid-March, and migration 

 continues through April (Bellrose 1976, Palmer 1976a). A few may depart as 

 early as late February or as late as early May (Palmer 1976b). 



HABITAT 



Nesting Throughout its breeding range in North America the Whistling Swan 

 is associated with Arctic tundra. Nest sites are typically widely dispersed 

 over the tundra, and small islands in tundra pools are preferred nesting sites. 

 Other nests are found elsewhere in the tundra, sometimes well removed from 

 water (Palmer 1976a, Bellrose 1976). Lensink (in Bellrose 1976) estimated that 

 about half the swan nests in coastal areas of the Yukon Delta were on the shores 

 of lakes or ponds within 60 ft (18 m) of water. Some 30% of the remainder were 

 on small islands or points in lakes; the rest were in a variety of situations, 

 such as heath tundra, marshes, or tidal meadows. In the latter, the swans fre- 

 quently nested on elevated hummocks, and nests were less common in level areas, 

 whistling Swans are usually absent from the bare areas of the Pre-Cambrian 

 Shield in central and eastern Canada (Johnsgard 1975). 



Feeding Detailed studies of feeding habitat, at least in the east, have 

 not been made. Swans wintering in Chesapeake Bay prefer brackish estuarine 

 bays, but they have been found feeding in California in both dry and flooded 

 fields (Bellrose 1976). During the early 1970's, swans wintering in the Chesa- 

 peake Bay area fed less in aquatic habitats and began to feed regularly in 

 fields of waste corn ( Zea ). , soybeans ( Glycine ) , and shoots of winter wheat ( Tri - 

 ticum ) on the Maryland Eastern Shore; they commonly flew as much as 10-15 mi 

 (16-24 km) inland to feed there (Bellrose 1976). 



Winter Wintering birds prefer large, shallow expanses of fresh and brack- 



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