Natal forest fragment size does not predict fledgling, pre-migration or apparent annual survival in Wood Thrushes
ORNITHOLOGICAL APPLICATIONS(2024)
摘要
Determining the drivers and mechanisms for first year survival of migratory songbirds has been an understudied area in population dynamics due to the difficulty in tracking juveniles once they have dispersed from the natal site. With the advancement in miniaturization of radio-tags (battery life similar to 400 days) and the development of the Motus Wildlife Tracking System, we tracked 189 Wood Thrush (Hylocichla mustelina) nestlings through independence and to fall migration departure, and their return the following spring. Natal forest fragment size and landscape forest cover (at different spatial scales) were not strong predictors of fledgling, pre-migration, or apparent annual survival; and onset of fall migration was best predicted by fledge date but not natal fragment size. Survival probability was lowest the first 16 days post-fledging (70%, or 0.86 weekly survival probability), very high for juveniles as they explored the landscape prior to fall migration (89%, or 0.99 weekly survival probability) and low during their first migration and wintering season (26%, or 0.95 weekly survival probability). To our knowledge, this is the first study to directly estimate annual apparent juvenile survival in a migratory songbird using year-round radio-tracking. Our study suggests that small forest fragments are important for the conservation for forest songbirds because they can support high survival of juveniles.
更多查看译文
关键词
apparent juvenile survival,fall migration timing,fledgling survival,fragment size,Motus,pre-migration survival,Wood Thrush
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要