SEGURA Luciano Noel
Nest survival of Red-crested Cardinals increases with nest age in south temperate forests of Argentina
SEGURA, LUCIANO N.; REBOREDA, JUAN C.
JOURNAL OF FIELD ORNITHOLOGY
WILEY-BLACKWELL PUBLISHING, INC
Año: 2012 vol. 83 p. 343 - 350
To understand nest survival is critical to bird conservation and to study avian life history. The available information on nest survival for Neotropical birds is scarce, particularly in south temperate regions. We modeled daily survival rates (DSR) of Red-crested Cardinal (Paroaria coronata, Thraupidae) nests in a native south temperate forest in the center of Argentina by using program MARK. We tested whether vulnerability to predation during the eggs and nestlings stages increases with age of the nest, controlling for the effects of physical characteristics of the nest site and progression of the breeding season. We monitored 327 nests for a total of 2479 exposure days during the eggs stage, and 192 nests for a total of 1572 exposure days during the nestlings stage. During the eggs stage DSR increased with age of the nest, decreased with time of breeding and it was higher for nests located in isolated patches of forests. During the nestlings stage DSR increased with age of the nest and cover of the tree canopy around the nest. Cumulative probabilities of nest survival during the eggs and nestlings stages were 0.34 and 0.39, respectively, and nest survival along the nesting cycle was 0.13. The increase of DSR with nest age could be the consequence of more vulnerable nests depredated early in the nesting cycle, or parents defending more vigorously the nest as nestlings approach fledging age. Nest survival rates reported in this study are considerably lower than those recorded in tropical or Neartic temperate birds, but similar to those of other studies conducted in Neotropical temperate birds.