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.

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

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

YEARS

FIGURE 5.-Duck breeding populations in North America, 1955-66 (adjusted for visibility bias and excludes scoters, eiders, mergansers and oldsquaw).

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

YEARS

FIGURE 6.—Mallard, pintail and blue-winged teal breeding population indexes, 1955-66 (adjusted for birds not recorded by the aerial crews).

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

YEARS

FIGURE 7.-Canvasback and redhead breeding population indexes, 1955-66 (unadjusted for birds not recorded by aerial crews).

FIGURE 8.-Duck flight forecast, change in 1966 from 1965.