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of black ducks from this region will probably not be much changed from 1965. Indirect estimates of wood duck populations suggest that this species is in good shape. From western areas supplying the Atlantic Flyway, there should be an increase in the contribution to the fall flight (figure 12). Consequently, we conclude that there will be little change in the numbers of black ducks available to all flyway hunters but there will be a slight increase in the fall flight of all ducks in the Atlantic Flyway compared to 1965.

Geese.-Winter survey data suggest that there was a good increase in the Atlantic Flyway population of Canada geese. This quite large wintering population of geese occurred following a hunting season where the kill was very low. If reasonable production among these birds occurred this summer then the fall flight in 1966 of Canada geese in the Atlantic Flyway should exceed that of 1965. The Atlantic snow goose population despite extremely poor reproductive success (as evaluated by John Lynch), apparently held its own between 1965 and 1966 showing only a 7 percent decrease.

Coots. If we assume that the Dakotas and western Minnesota do not supply many coots to the Atlantic Flyway, there will probably be little change or perhaps a small decrease in the flight of coots in 1965.

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TABLE 2.-Duck breeding population indexes from aerial survey, 1965–661

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1 Not adjusted for visibility bias and excluding scoters, eiders, mergansers, and oldsquaw.

TABLE 3.-Goose and brant winter survey indexes by flyway, 1965–661

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TABLE 4-Breeding population indexes of coots, 1956–66 (not adjusted for

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1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966

FIGURE 1.-Mallard population dynamics, 1955-66.

PERCENT

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FIGURE 2.-Relationship between percent shot and total mortality rate for mallards, 1955-65.

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MILLIONS OF WATER AREAS

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1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966

YEARS

FIGURE 3.-Numbers of water areas in the southern portions of Alberta, Saskatchewan, and Manitoba, 1951-66.

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FIGURE 4.-Numbers of water areas in southern Canada, North Dakota, South Dakota, and Minnesota, 1959-66.

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