Populations increased in the 1960s and then declined steadily to 
a low of 10,700 in 1982. The long-term average population size 
was 65,909. In the 1980s, the population was 28,973 which was 
61% lower than the pre-1980s average of 73,988. Trends of scaup 
populations in the Chesapeake Bay have not been similar to those 
in North America and the Atlantic Flyway. For unknown reasons 
scaup populations in the Chesapeake Bay in the early 1960s did 
not reflect the record 2.6 million recorded throughout North 
America. 
Historically, scaup have fed on molluscs and crustaceans 
(Stewart 1962, Munro and Perry 1981), and current food habits 
indicate similar food preferences. It is doubtful whether the 
loss of SAV in the Bay has significantly affected the distribu¬ 
tion or abundance of scaup, although the diversity of inverte¬ 
brate food organisms has probably declined due to the loss of 
SAV (Perry et al. 1981). 
Common Goldeneye 
The goldeneye (Bucephala clangula) is a hole-nesting duck 
that breeds in the forested wetlands of southern Canada. Winter¬ 
ing populations in the Chesapeake Bay peaked in 1956 at 40,518 
and reached a low in 1976 at 2,445 (Table 1; Fig. 7). The long¬ 
term average population in the Bay is 19,659. In the 1980s the 
average population in the Bay has been 17,513 which is 13% lower 
than the pre-1980s average of 20,128. Trends of goldeneye popu¬ 
lations in North America and Atlantic Flyway have been similar 
during survey years. 
Goldeneye feed mainly on invertebrates (Stewart 1962, Munro 
and Perry 1981), and changes in the distribution and abundance 
of SAV have probably not affected goldeneye populations. The 
amount of vegetation eaten by goldeneye has declined, however, 
during the hundred years in which food habits analyses have been 
conducted. 
Bufflehead 
Although the bufflehead (Bucephala albeola) and goldeneye 
both breed and winter in similar habitat, their wintering popu¬ 
lation trends are different (Table 1; Fig. 7). Bufflehead 
numbers have been steadily increasing from a low of 2,502 in 
1959 to a peak of 36,023 in 1977. The long-term average popu¬ 
lation was 14,813. During the 1980s the average population was 
16,840 ducks which was 17% higher than the pre-1980s average of 
14,444. Population trends in the Chesapeake Bay have been 
similar to those in the Atlantic Fiyway and in North America for 
the bufflehead. 
152 
