Neck Bands Reduce Survival of Canada Geese in New Jersey

We examined the effect of neck bands on the survival and recovery rates of Canada geese (Branta canadensis) breeding in New Jersey. A total of 8,082 geese were legbanded and 3,428 geese were neck- and legbanded from 1984 through 1989 during June-July throughout New Jersey. Our analysis suggested that survival rates did not differ between adults and immatures within either group (P > 0.05). However, there was evidence that survival did differ between the 2 methods of marking (P < 0.01). The average annual survival rate was estimated as 82.77% (SE = 3.17%) for geese with leg bands only and 69.21% (SE = 3.66%) for geese banded with both leg and neck bands. The use of neck-band observations to estimate annual or period survival rates requires an assumption that neck bands do not influence survival rates. In our study, this assumption appeared to be violated. Managers should use caution in interpreting the results of existing neck-banding studies. Neck bands should be used judiciously and, when possible, with a leg-banded only control group.