Age effects on survival of Amazon forest birds and the latitudinal gradient in bird survival

• DOI: 10.1642/auk-17-91.1
• Publication Date: 2018-03-07T15:44:33Z
• Authors: Alejandra Pizarro...; Marc Kéry; Pedro Vitor Martins; Gonçalo Ferraz
• Keywords: Avian clutch size; Understory

The search for explanations of the well-documented positive relationship between latitude and avian clutch size has created expectation that tropical birds should balance their smaller sizes with relatively high survival probabilities. So far, efforts to detect a latitudinal gradient in have found no statistical support, leading hypothesis may be present juveniles alone. Such could masked by data on adults when field records make distinction ages. We aimed (1) assess effect age estimating age-specific annual apparent probabilities set 40 passerine understory species from central Brazilian Amazon (2) test adult meta-analysis temperate-zone forest at study areas Peru Alaska. estimated using hierarchical, multispecies Cormack-Jolly-Seber (CJS) model treats species-specific parameters as random effects. To extend our analysis unknown time banding, we developed novel CJS mixture component age. strong site, having lower than adults. 342 estimates 175 span >60 degrees revealed negative survival, which supports widely accepted that, average, higher temperate counterparts. conclude there is need an alternative trend juvenile account general size.