Population Characteristics and Simulation Modeling of Black Ducks.

摘要

Excessive black duck harvest has been implicated in the decline of the black duck population as evidenced by Winter Survey trends. A review of literature about black duck distribution, migration, and population dynamics is presented. The preseason and winter banding and recovery files are described and their limitations are discussed. Twenty-seven preseason major reference areas of banding and 15 winter major reference areas of banding are defined. Deterministic and stochastic models are used to evaluate population estimates. The population sex ratio is estimated to be 1.20 to 1.38 males per female. The effects of small changes in parameter values are explored. Corrections for positive bias in the survival and production estimates are required to produce a Continental Black Duck Population trajectory that tracks the population curve derived from Winter Survey data. Management recommendations are presented relative to hunting regulations and to banding programs.