Counts reported about 150 wintering in Nova Scotia, New Brunswick, and Quebec. 

 About 53.4% of the 90,000 Buffleheads reported by Johnsgard (1975) winter in 

 the Atlantic Flyway with another 35.6% in the Pacific Flyway, 6.2% in the Mis- 

 sissippi Flyway, and about 4.6% in the Central Flyway. The proportions for the 

 Pacific and Central flyways include counts for the west coast of Mexico and for 

 the interior and east coast of Mexico, respectively. 



About 90,850 Buffleheads were found on the 1975 winter waterfowl survey, 

 5,990 of which were in Mexico (Goldsberry et al. 1980). The proportions found 

 in the Pacific (29.9%) and Atlantic (52.1%) flyways were similar to those re- 

 ported by Johnsgard (1975), but the proportion in the Central Flyway (15.7%) 

 was considerably larger, principally because of the large number reported from 

 Texas. The Mississippi Flyway held the remaining 2.3%. Proportions found in 

 each flyway during the 1976 survey (Larned et al. 1980) were roughly similar, 

 but the proportion in the Central Flyway (8.9%) was, as in the preceding year, 

 greater than in the Mississippi Flyway (4.6%) , suggesting that there may have 

 been a change in the winter distribution of the Bufflehead in the southeast. 



In 1975 the southeastern United States harbored 12,820 (ca. 14.1%) of the 

 total found on the winter survey; about 60% of the Buffleheads in the southeast 

 were found in Texas, which held the fifth largest wintering population. The 

 largest wintering populations were found in Maryland (14,300), Washington 

 (13,686), New Jersey (12,260) and California (7,877). Figures provided earlier 

 by Bellrose (1976) suggested that roughly 19% of the population wintering in 

 the contiguous United States and Mexico was found in the southeastern United 

 States. The largest numbers of wintering birds were found in Washington (ca. 

 15,000), New Jersey (9,900), Maryland (8,800), North Carolina (7,100) and 

 Texas (4,300). 



Migration During fall migration most Buffleheads migrate from their breed- 

 ing grounds in northwestern North America either southwest to the Pacific coast 

 or southeast to the north Atlantic coast (Bellrose 1976). Erskine (1972) point- 

 ed out that the migratory pathways divide in Alberta. From a triangular area 

 about 150 mi (241 km) across at its base near 54° N latitude, Buffleheads may 

 follow a variety of routes; this area is the source of most birds migrating 

 south. Almost all Buffleheads to the west of this area migrate southwest and 

 most of those to the east move southeast. 



Considerably less is known about routes employed by migrating Buffleheads 

 during the spring because relatively few birds are banded during the winter and 

 only a few are shot (illegally) during the spring. The routes taken may well 

 be very similar to those employed in fall (Erskine 1972). 



Erskine (1972) provided the most information on Bufflehead migration and 

 his work has been ably summarized by Palmer (1976b) and Bellrose (1976). By 

 February, wintering Buffleheads may be moving north along the Atlantic coast to 

 the areas from which they will migrate overland to the breeding grounds. Most 

 will have left the Gulf and southeastern Atlantic coasts by March. During fall 

 migration the major movement by migrating Buffleheads apparently occurs in late 

 October and early November with most of these ducks reaching their wintering 

 grounds during December (Palmer 1976b). Bellrose (1976), Palmer (1976b), and 

 especially Erskine (1972) should be consulted for further details on migration 



410 



