with extreme dates of occurrence from mid-October to late April. These ducks 

 occur throughout the state but are most frequent in the deepest lakes and bays 

 (Lowery 1974). As in Mississippi, none were reported during the 1975 winter 

 waterfowl census (Goldsberry et al. 1980), but slightly more than 800 were 

 shot by hunters the preceding hunting season (Larned et al. 1980). 



Texas The Bufflehead occurs in Texas from early November to late April as 

 a winter resident. Oberholser (1974) considered the species locally common to 

 scarce in the western half of the state and uncommon to rare in the eastern 

 half. Bellrose (1976) reported that the average seen on winter surveys was 

 4,300 Buffleheads. These ducks may now be more common along the Texas coast 

 than this information suggests. Blacklock (1978 ms) considered the species 

 common in winter, with peak densities present from December to February. Golds- 

 berry et al. (1980) reported 7,730 Buffleheads during the 1975 winter survey of 

 Texas; this was more than twice that reported for all of the other southeastern 

 states. In addition, average Christmas Bird Counts for recent years were larger 

 along the southern Texas coast than anywhere else in the southeast (Map 29). 



SYNOPSIS OF PRESENT DISTRIBUTION AND ABUNDANCE 



Breeding The Bufflehead breeds solely in North America. It breeds from 

 central Alaska east through the Yukon Territory and northern Mackenzie District, 

 across British Columbia, Alberta, Saskatchewan, and Manitoba, to Ontario, and 

 probably into Quebec. It breeds south only as far as northern Idaho and north- 

 western Montana (AOU 1957, Erskine 1972, Palmer 1976b). Isolated breeding popu- 

 lations occur in central Oregon, northeastern California, northwestern Wyoming, 

 and northern and eastern Idaho (AOU 1957, Palmer 1976b, Lannoy and Sakaguchi 

 1979). 



Erskine (1972) suggested a range of between one-quarter and three-quarters 

 of a million birds in the spring population of Buffleheads in North America. 

 Bellrose (1976) analyzed additional breeding ground surveys and indicated that 

 the spring pre-breeding population was about 745,000 birds; Erskine' s earlier 

 analysis of the same kind of data had resulted in an estimate of 500,000. A 

 majority of the population (423,000 birds) is found in the closed boreal forest 

 and extensive parklands of the Canadian Prairie Provinces but the greatest den- 

 sities (10 per sq mi) are found in the Cariboo District of British Columbia 

 (Bellrose 1976). A survey of part of the breeding grounds in 1976 (Larned et 

 al. 1980) revealed a population of about 896,000 birds. Nearly half (45.1%) of 

 these were in northern Alberta, northeastern British Columbia, and the North- 

 west Territories. Substantial numbers were also found in northern Saskatchewan, 

 northern Manitoba, and the Saskatchewan River Delta (30.3%), and in Alaska 

 (13.1%). 



Winter Buffleheads winter along the Pacific coast from the Aleutians to 

 Sinaloa on the central Mexican coast, and along the Atlantic coast from Nova 

 Scotia and New Brunswick south (Map 29) to northern Florida and the Gulf coast 

 as far as Tamaulipas (AOU 1957); they are also found in larger inland lakes 

 (Bellrose 1976). In 1966-69, winter surveys by the U.S. Fish and Wildlife Ser- 

 vice found 90,000 Buffleheads (Johnsgard 1975). Bellrose (1976) indicated that 

 nearly 13,000 more winter on Alaskan refuges and that Audubon Christmas Bird 



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