Survival and Longevity of the Little Brown Bat (Myotis lucifugus) in Southeastern Ontario

Abstract
Survival and longevity in a hibernating population of Myotis lucifugus were studied for 35 years with mark-recapture techniques. Two males were recaptured 29 and 30 years after being banded; these two bats showed no outward signs of senescence. Survival rates were calculated with Cormack's stochastic technique. Average annual survival rates were 0.816 for males and 0.708 for females. Climatic and geographic factors may account for differences in survival rates between populations in Ontario and in southern Indiana, where female survival rate exceeds male. The differences in survival rate between the sexes are not alone sufficient to account for the male-skewed sex ratios in hibernating populations.