Microhabitat Nest Cover Effect on Nest Survival of the Red-Crested Cardinal

Abstract

We evaluated the influence of microhabitat vegetation cover on Red-crested Cardinal (Paroaria coronata) nest survival in natural forests in central eastern Argentina by monitoring 106 nests for 1,262 exposure days. Daily nest survival rates increased with vegetation cover above the nest and decreased linearly as the breeding season progressed. Increased concealment above the nest helped hide and protect nests from predators (mainly aerial predators). Earlier nesting attempts in the breeding season were more successful than those later in the season. This is the first study to evaluate the effect of microhabitat vegetation cover on daily nest survival rates of a south temperate passerine. We highlight the importance of microhabitat nest concealment on nest success of the Red-crested Cardinal.