Waterfowl status report, 1981.

The Waterfowl Status Report, 1981, is a standard compilation of survey data provided by State, Federal, Mexican, and Canadian wildlife agencies. Three specific surveys were used: the 1980-81 midwinter waterfowl survey by flyway, the breeding waterfowl and habitat surveys for 1981 (United States and Canada), and the 1981 waterfowl harvest survey (United States) for the 1980-81 hunting season. Winter surveys completed during December 1980 (mid-December goose count) and January 1981 (all species except geese surveyed in the December count) showed decline in most duck species in the Pacific Flyway and greater-than-normal concentrations of waterfowl in Washington and Idaho. In the Central Flyway, declines were noted for most waterfowl with the exception of the mallard (Anas platyrhynchos). A small increase (8%) in duck numbers was reported for the Mississippi Flyway wintering areas; large accumulations of ice and below-normal temperatures concentrated waterfowl in the Atlantic Flyway, resulting in higher-than-normal counts for the region. The 1981 breeding waterfowl and habitat surveys were completed with spring weather similar to that reported for 1980. The warm and dry conditions contributed to a low May pond index (33% below 1980 and 33% less than the previous 12-year average) computed for the prairie Provinces (Canada) and northern United States. Spring was early in the northern breeding areas, where pond counts were reduced also. Most prairie-parkland areas received rain in late May and June; however, by early July dry conditions again prevailed. The loss of surface water was substantial between May and July 1981 causing the July pond count to decline 3% from the 1980 count and 47% below the long-term average. The 1981 duck breeding population was 9% below that of 1980 and 5% below average. Substantial increases in duck number from 1980 were reported for areas in Colorado, California, and Wisconsin, whereas smaller gains were reported in northern Saskatchewan and Manitoba, southern Manitoba, and Montana. Estimates decreased by 18% in the remaining prairie Provinces and 28% in North Dakota and South Dakota from 1980. The numerically important mallard declined 16% from 1980 and 22% from the average. Production indices for prairie and parkland areas declined 31% from 1980 and were 55% less than the average; however, the late-nesting index increased for most areas, suggesting an improvement in late-nesting effort by ducks. Waterfowl harvest survey estimates of the number of immatures per adult in the harvest (age ratio) were lower (0.98 immatures per adult) during the 1980-81 hunting season than those of the previous year (1.41 immatures per adult). The total duck kill also declined from the previous year, but the mallard harvest changed only slightly from that of the previous hunting year (1979-80).