NECK BAND LOSS RATES FOR LESSER SNOW GEESE

Band loss is often assumed to be negligible when resightings of neck-banded birds are used to estimate population parameters. Neck band loss rates (M, 0.47; F, 0.17) for lesser snow geese (Chen caerulescens caerulescens) were estimated for 1981-90 in the Sagavanirktok River Delta, Alaska. Neck band loss was substantial and comparable with or higher than rates reported for several Canada goose (Branta canadensis) populations. Nearly 60% of neck bands lost were found broken near nest sites, indicating that the majority of bands was lost when birds returned to the Arctic to breed, rather than during migration or winter. Annual neck band loss rates increased (P < 0.001) with neck band age, and rates were higher (P < 0.001) for males than for females. Loss rates of replacement neck bands were higher than for first neck bands (P < 0.01). Maximum neck band retention by males and females was 3 and 7 years, respectively, even though some snow geese survived for the entire 10-year study. Neck band resighting data should not be used to estimate demographic traits, such as survival, without considering neck band loss.