Nesting biology of the Spotted Nightingale-Thrush (Catharus dryas) and comparison of life histories in the genus Catharus

Abstract

ABSTRACT Elucidating new reproductive traits and evaluating how they vary within and among species in a geographic context, is relevant to understanding the evolutionary processes underlying diversity in life-history strategies. In this study we describe the breeding biology of Catharus dryas in a Peruvian population, and compare life history traits with a subtropical population and other temperate Catharus thrushes to better understand intra and interspecific variations in nesting traits. We monitored 35 nests of C. dryas between 2008 and 2013 in an Andean cloud forest of the Manu National Park in Peru and conducted a literature review of the nesting biology of Catharus species. We provide new information on nest architecture, nestling growth rate, incubation behaviour, reproductive phenology and egg temperature. The intraspecific comparison with an Argentinian population showed that despite the 13° latitudinal differences, nesting characters were highly conserved. These include a clutch size of two eggs, and an incubation and nestling period of 14 days. Nest attendance differed slightly (60 and 67% in Peru and Argentina, respectively). The interspecific comparisons showed that tropical and temperate species followed respectively slow and fast reproductive strategies in most of the traits according to the life-history theory, but other such as average incubation time, nestling feeding rate, and some dimensions in the nest architecture were similar between C. dryas and the temperate species. Although detailed descriptions are needed for Catharus species, especially tropical species to conduct more robust comparisons, our results exemplify how intra and interspecific comparison based on natural history data can help to understand life-history evolution in a biogeographic context.