Survival Rate of the Long-Tailed Jaeger at Alert, Ellesmere Island, Nunavut

[摘要] Abstract. In long-lived animals, survival rate is a key demographic parameter affecting population dynamics. The objective of this study was to estimate the apparent survival rate of adult Long-tailed Jaegers (Stercorarius longicaudus) breeding at one of the most northerly sites on earth, northern Ellesmere Island, Canada. Because of the large temporal fluctuations in numbers of lemmings, their primary food source during the summer, we also investigated the effect of annual variations in lemming abundance on survival rate. Analysis was based on 336 individuals marked as adults over 11 years with metal and color bands and capture—mark—recapture techniques. There was strong support for a model with two age classes, as survival of newly marked birds was 18% lower than that of previously marked ones. This difference could be due to a true age effect (if a high proportion of young adults was present in our initial samples) or, perhaps more likely, to the presence of transient individuals in the population. The...

[学科分类] 动物科学

[关键词] lemming;Long-tailed Jaeger;seabird;Stercorarius longicaudus;survival;transient;tundra