Band recovery and recapture rates of American black ducks and Mallards

Data from band recoveries and recapture rates are essential for testing influences on key demographic parameters of avian populations. I used recaptures and recoveries of leg-banded birds to test the influence of condition on the probability of survival and to compare site fidelity of American black ducks (Anal rubripes) and mallards (A. platyrhynchos) to the wetlands of southwestern Lake Erie. I live-trapped and banded 996 black ducks and 1,168 mallards from October through January during 3 annual staging periods (1990-1993) on Ottawa National Wildlife Refuge (NWR) in Ohio, USA. Ducks were aged, sexed, and weighed; total body length, wing chord, culmen, and tarsus also were measured to compute condition indices. I used multiple-logistic regression models to test influences of condition, date of initial capture, and species on the probabilities of recapture and band recovery for each age-sex class, Black ducks were more likely to be recaptured than mallards in all age-sex classes within a season and during subsequent seasons. Body condition had a positive influence on recaptures during subsequent field seasons for adults. Analyses of within-season band recovery for adult males of both species indicated that birds with lower condition were more likely to be harvested. The opposite relationships between condition and the probability of recapture and direct recovery support the contention that poor body condition increased vulnerability to hunting for adult males.