Birds of Indian Subcontinent

Pair copulation frequency correlates with female reproductive performance in Tree Sparrows Passer montanus

Publication Type:Journal Article
Year of Publication:2001
Journal:Journal of Avian Biology
Date Published:2001
ISBN Number:1600-048X
Keywords:Passer, Passer montanus, Passeridae, Salicipasser montanus
Abstract:In socially monogamous birds, males benefit from frequent copulations with their partner if this increases their paternity in the brood. By soliciting and accepting copulation attempts, female birds can control pair copulation frequencies. Engaging in copulations can be costly by taking up time and by increasing the risks of predation and pathogen transmission. Current hypotheses propose that high pair-copulation frequencies may compensate for these costs by providing females with direct benefits that can result in higher reproductive success. In this study, I examine in a Tree Sparrow population the prediction that high pair-copulation frequencies are associated with better female reproductive performance. The results show that clutch sizes laid were positively correlated with the pair-copulation frequency. The length of the incubation period was negatively correlated and, as expected, the number of fledglings was positively correlated with pair-copulation frequency. The results are consistent with current hypotheses for the evolution of frequent pair copulations and provide one of the few evidences for a positive relation between pair-copulation frequency and female reproductive performance. This study also suggests that within-pair copulation frequency could be an early expression of the pairs’ reproductive ability and might signal their phenotypic quality.
Short Title:Journal of Avian Biology
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith