Application of a Habitat Suitability Index Model for Wintering Black Ducks

The Habitat Suitability Index (HSI) model (Lewis and Garrison 1984) for wintering American black ducks (Anas rubripes) was applied during 1985 and 1986 at Chincoteague, Virginia. HSI values of 0.66 and 0.56 were obtained during the 2 respective years. We suggested improvements in field methods for estimating biological variables. Modification of 1 variable (V6) and inclusion of a new variable (proportion of total land and water represented by saltmarsh, Vg) were proposed to improve model output.