predominant foods in brackish estuarine bays 
(table 118), where the more important vege- 
table foods again included eelgrass and bait 
corn, Submerged plants and mollusks both were 
principal foods in the fresh estuarine bays 
(table 119); the commonest items included the 
leaves, stems and rootstalks of wildcelery, 
seeds of pondweeds and the gastropod 
Oxytrema virginica. The single Greater Scaup 
collected on Chincoteague Bay had fed en- 
tirely on the bivalve mollusk Tagelus divisus. 
Local Distribution of Hunting Kill 
Information concerning local distribution of 
the hunting kill of Greater Scaup within the 
Upper Chesapeake region was obtained through 
an analysis of the distribution of 19 weighted 
recoveries of birds banded outside Maryland 
and Virginia. Nine of these recoveries were 
reported during the 1956 season and ten during 
1957. 
The distribution of the kill was as follows: 
Chester River section - 31%; Lower Eastern 
Shore section - 27%; Central Western Shore 
section - 17%; Susquehanna Flats section - 
10%; Eastern Bay section - 10%; and Coastal 
section - 5%, Approximately two-thirds of the 
total kill was in the eastern shore area, from 
the Chester River to Pocomoke Sound, Kill data 
arranged by habitat types show that 58% of the 
kill occurred on brackish estuarine bays, 27% 
on salt estuarine bays, 10% on fresh and 
slightly brackish estuarine bays, and 5% on 
coastal bays. Data arranged by months show 
that 33% of the kill occurred in November, 45% 
in December, and 22% in January. 
a 
Harvest Areas of Birds Banded in Upper 
Chesapeake Region 
Data concerning harvest areas of Greater 
Scaup banded in the Chester River, Eastern 
Bay, Solomons, and Sandy Point (Anne Arundel 
Co.) areas during the years 1954-58 came 
from 37 indirect recoveries (table 120), All 
of the recovered birds were banded between 
January 29 and May 4. About four-fifths of 
the kill occurred in the coastal States from 
New York to North Carolina. About one-half 
of the total kill was in Maryland alone. Other 
fairly important harvest areas were in the 
Great Lakes-St. Lawrence section; greatest 
local concentration of kill was in Quebec. 
LESSER SCAUP 
Aythya affinis (Eyton) 
Migrant and wintering Lesser Scaup fluc- 
tuate more widely in numbers than do any 
other species of waterfowl in the Upper 
Chesapeake region. In many years, Lesser 
53 
Scaup are abundant and widespread; during 
occasional years, they are scarce and much 
more local. 
Population estimates of Greater and Lesser 
Scaup were combined because of the difficulty 
in distinguishing the two species during the 
aerial surveys. During the migration periods, 
and during most winters (those characterized 
by moderate or mild weather conditions), the 
Lesser Scaup ordinarily is the morenumerous. 
January inventories for 1953-58 show that the 
wintering scaup population (both species com- 
bined) ranged from 14,300 in 1958 to 347,600 
in 1954, averaged approximately 113,000. This 
average figure represents about 6% of the 
continental wintering population, and about 13% 
of the Atlantic population. 
The fall migration usually takes place during 
the period from September 25 - October 5 to 
December 15-25, with the peak between 
November 10 and December 10. The normal 
spring migration period extends from March 
1-10 to May 10-20, with the peak between 
March 15 and April 20. 
Habitats 
The larger migrant populations of Lesser 
Scaup generally are restricted to fresh, slightly 
brackish, and brackish estuarine bays. Small 
numbers usually are scattered over the salt 
estuarine bays and occasionally a few migrant 
flocks occur on interior impoundments, par- 
ticularly during the spring flight. During most 
years, brackish estuarine bays are the chief 
wintering habitat. The ecological distribution 
of Lesser Scaup is not closely correlated with 
the occurrence of submerged plants, differing 
in this respect from most other species of 
waterfowl. 
January inventories for the period 1955-58 
showed the following distribution of wintering 
scaup populations (Greater and Lesser Scaup 
combined): brackish estuarine bays - 73%; 
coastal bays - 11%; salt estuarine bays - 7%; 
slightly brackish estuarine bays - 7%; andfresh 
estuarine bays - 2%, 
The ecological distribution of scaup popula- 
tions (both species combined) during the 1958- 
59 season is shown in table 12]. Over two- 
thirds of the migrants during early November 
were in the fresh estuarine bays. The largest 
concentration of late fall and early spring mi- 
grants was in brackish estuarine bays, and 
fairly large numbers were in fresh, slightly 
brackish, and salt estuarine bays. The un- 
usually high wintering concentrations of scaup 
in the salt estuarine bays was a result of the 
unusually severe weather conditions thatyear. 
Biogeographic Sections 
The average distribution of scaup during 
the January inventories of 1955-58 is shown 
