A meta-analysis of global avian survival across species and latitude

Tropical birds are thought to be longer lived than many temperate species. We explored the idea of higher survival at tropical latitudes and whether extrinsic climate factors and intrinsic traits helped explain this pattern using a meta-analytical approach. The dataset consists of 949 estimates from 204 studies of avian survival from both New World and Old World biogeographical realms.

Methods
Data were collected from the primary literature using Web of Science Core Collections and Google Scholar. We extracted data on survival and its associated standard error from each paper, as well as information on the study location and species intrinsic traits. When information on species traits was not included in the publication, we used data from standard reference databases (i.e., Handbook of Birds of the World, Elton Traits database). All climatic variables were downloaded from WorldClim.