Evaluation of aerial transect surveys for wintering American black ducks

Journal of Wildlife Management
By: , and 



We used an experimental aerial transect survey with stratified random sampling, to estimate the size of the population of wintering black ducks (Anas rubripes) in coastal New Jersey during 2 winters, and the coastal Atlantic Flyway (Me. to S.C.) during 4 years. Population estimates were precise (CV < 0.20) on a flyway basis, whereas individual strata (states) had coefficients of variation of 0.16-0.71. Population estimates agreed with the conventional mid-winter waterfowl surveys (MWS) for all 4 years (MWS within 95% CI of N). We recommend continuing these surveys to provide precise and statistically defensible population estimates for black ducks. Additional improvements in precision may be achieved using recent developments in estimation such as Bayesian techniques. Techniques to decrease bias through air-ground comparisons are likely to be expensive and will require more development. Air-ground comparisons can probably be justified if there is a demonstrable need for an estimate of the absolute size of the black duck population versus an index.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Evaluation of aerial transect surveys for wintering American black ducks
Series title Journal of Wildlife Management
Volume 52
Issue 4
Year Published 1988
Language English
Contributing office(s) Patuxent Wildlife Research Center
Description 694-703
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Journal of Wildlife Management
First page 694
Last page 703