Juvenile Survival in a Neotropical Migratory Songbird Is Lower than Expected

摘要: Attempts to estimate and identify factors influencing first-year survival in passerines, between fledging the first reproductive attempt (i.e. juvenile survival), have largely been confounded by natal dispersal, particularly long-distance migratory passerines. We studied Prothonotary Warblers (Protonotaria citrea) breeding nest boxes while accounting for biases related dispersal that are common mark-recapture studies. The distribution (median = 1420 m; n = 429) a distance-dependent recruitment rate, which controls effects of study site configuration, both indicated pattern short-distance dispersal. This was consistent with results systematic survey birds returning outside box sites (up 30 km all directions) within majority (81%) total available bottomland forest habitat, further suggesting permanent emigration system rare. used multistate modeling incorporated thought influence potential confounding on recapture probabilities warblers fledged during 2004–2009 (n = 6093). Overall, average reared without cowbird nestmates 0.11 (95% CI = 0.09–0.13), decreased date (0.22 early 0.03 late) averaged 40% lower brood parasite nestmate. First-year less than half rate represent population replacement passerines (∼0.30). very low suggests surviving year life many Neotropical species is even more difficult previously thought, forcing us rethink estimates models.