recently declined along the Gulf coast . 



Bellrose (1976) reported winter populations for the state of about 2,300, 

 most of them on Mobile Bay; the most recent count available (1975) found only 

 200 birds (Goldsberry et al. 1980). 



Mississippi Burleigh (1944) saw small flocks of Canvasbacks only in Octo- 

 ber and November along the Mississippi coast, but there are a few records of 

 late migrants and summering birds for the period for April through July as well 

 (Imhof 1973, 1975; Jackson and Cooley 1978b). Information provided by Bellrose 

 (1976) indicated some 4,400 winter in Mississippi, mostly at Sardis Lake (in- 

 land) and on the coastal bays. More recently, mid-winter rafts of 1,600 (1977) 

 and 1,000 (1978) have been reported at Lake Washington, in the interior portion 

 of the state (Jackson and Weber 1977, Jackson and Cooley 1978a). The January 

 1975 waterfowl count found few birds in Mississippi. 



Louisiana The Canvasback is a regular winter resident in Louisiana, usu- 

 ally arriving in the state in late October and departing during April (Lowery 

 1974). Bellrose (1976) reported that 15,000 winter there, most of them near 

 Morgan City on Six Mile and Wax lakes. The 1975 winter survey reported only 

 1,000 birds (Goldsberry et al. 1980). The survey of Louisiana was incomplete, 

 however, and it seems likely that a number of birds were overlooked. 



Texas Oberholser (1974) noted that the Canvasback is irregularly very com- 

 mon on the Texas coast. It is most numerous in the northern half of the state 

 in spring and fall. These ducks generally are seen from mid-October to early 

 May. Bellrose (1976) indicated wintering populations of about 9,400, half in- 

 land and half on the coast. The January 1975 survey listed 25,810 (Goldsberry 

 et al. 1980). 



SYNOPSIS OF PRESENT DISTRIBUTION AND ABUNDANCE 



Breeding Canvasbacks nest only in North America. Most breeding occurs 

 from northwestern Alaska south to south-central British Columbia, and southeast 

 to southern Manitoba, western Minnesota, and eastern South Dakota. The heart 

 of the breeding range is in the southern portions of Alberta, Saskatchewan, and 

 Manitoba. Of approximately 678,000 counted on the breeding grounds during the 

 1976 survey, 76% were found in these provinces (Larned et al. 1980). 



In recent years there has been considerable concern about the status of the 

 Canvasback. Numbers fluctuate widely from year to year and Bellrose (1976) con- 

 sidered it even more threatened than the Redhead. Declines in the population 

 have led to restrictive hunting regulations, both in the 1930' s and more recent- 

 ly. Poor nesting success has been attributed to high mortality rates, habitat 

 and range reduction, and increased nest predation (Trauger 1974 Ln White et al. 

 1979). Even now this species is still on the Blue-list (Arbib 1979), a list 

 that attempts to indicate species whose populations have declined so seriously 

 that they may become threatened or endangered. Johnsgard (1978) remarked that 

 unbalanced sex ratios, declining breeding habitat, sensitivity to oil and other 

 pollutants on the wintering grounds, and vulnerability to hunting make the fu- 

 ture of the Canvasback most uncertain. 



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