Estimates of Apparent Survival Rates for Forest Birds in Eastern Ecuador

Abstract

ABSTRACTKnowledge of survival rates of Neotropical landbirds remains limited, with estimates of apparent survival available from relatively few sites and species. We used capture–mark–recapture models to estimate apparent survival of 31 species from eastern Ecuador based on data collected from 2001 to 2006. Models assuming constant survival had highest support for 27 species; models incorporating effects of transients were highest for four. Average apparent survival across 30 species of passerines was 0.58 (± 0.02 SE); apparent survival was lower during the first interval after initial capture (φ1: mean = 0.49 ± 0.03) than during subsequent intervals (φ2: mean = 0.60 ± 0.02). Apparent survival was similar among three families represented by at least four species (Thamnophilidae: 0.57 ± 0.03, N= 10; Furnariidae: 0.59 ± 0.03, N= 5; Pipridae: 0.56 ± 0.02, N= 4). There was no indication that species that occur in flocks had higher survival than nonflocking species (obligate flock members: 0.57 ± 0.03, N= 10; facultative flock members: 0.56 ± 0.04, N= 5; nonflocking: 0.59 ± 0.03, N= 15). Comparisons of published estimates of apparent survival of tropical species demonstrated substantial differences among species and, in some cases, within species across different sites in the Neotropics. Our results support previous studies that concluded that early estimates of high (> 85%) survival in tropical birds may not be representative of all tropical species. Future studies should focus on understanding factors (e.g., life‐history traits) that promote differences in survival among species within tropical forests.