TY - JOUR
T1 - Breeding synchrony and extra-pair mating in red-winged blackbirds
AU - Weatherhead, Patrick J.
N1 - Funding Information:
Acknowledgements I thank D. Hoysak, P. Boag, R. Montgomerie, L. Gibbs, K. Muma, D. Michaud-Freeman, J. Sechley, C. Roeder, L. Hamilton, L. Tabak and S. Shackleton for technical assistance, Kevin Dufour, Bridget Stutchbury, Dave Westneat and Stephen Yezerinac for comments on the manuscript, Peter Boag for use of the Queen’s University Molecular Ecology Lab, the Lister Institute and Alec Jeffreys (University of Leicester) and T. Bargiello (Rockefeller Institute) for the probes used in DNA profiling, Queen’s University for the use of the Biological Station facilities and the Natural Sciences and Engineering Research Council of Canada and Carleton University for financial support.
PY - 1997/3
Y1 - 1997/3
N2 - Using data from a 6-year paternity study of red-winged blackbirds. I tested the hypotheses that increased nesting synchrony should either promote extra-pair mating by increasing the advantage of extra-pair mating to females, or decrease extra-pair mating by constraining males from seeking extra-pair copulations. Contrary to these hypotheses the occurrence of extra-pair paternity did not vary with nesting synchrony over the breeding season, or vary with the number of synchronous nests within territories or within marshes, or with nesting order on territories. However, for nearly all nests with extra-pair young, there were fewer females synchronous with that nest on the cuckolder's territory than on the territory of the cuckolded male. This 'advantage' of a synchrony difference was less pronounced for older males that cuckolded younger males, particularly when the two males were not neighbors. Collectively, these results suggest that breeding synchrony affects extra-pair mating by affecting mate guarding, but thai breeding synchrony alone can not be used to predict which females are more likely to engage in extra-pair mating, nor with which extra-pair males they will mate. Understanding why extra-pair mating by older males is less affected by breeding synchrony may explain much about both the proximate and ultimate causes of extra-pair mating in red-winged blackbirds.
AB - Using data from a 6-year paternity study of red-winged blackbirds. I tested the hypotheses that increased nesting synchrony should either promote extra-pair mating by increasing the advantage of extra-pair mating to females, or decrease extra-pair mating by constraining males from seeking extra-pair copulations. Contrary to these hypotheses the occurrence of extra-pair paternity did not vary with nesting synchrony over the breeding season, or vary with the number of synchronous nests within territories or within marshes, or with nesting order on territories. However, for nearly all nests with extra-pair young, there were fewer females synchronous with that nest on the cuckolder's territory than on the territory of the cuckolded male. This 'advantage' of a synchrony difference was less pronounced for older males that cuckolded younger males, particularly when the two males were not neighbors. Collectively, these results suggest that breeding synchrony affects extra-pair mating by affecting mate guarding, but thai breeding synchrony alone can not be used to predict which females are more likely to engage in extra-pair mating, nor with which extra-pair males they will mate. Understanding why extra-pair mating by older males is less affected by breeding synchrony may explain much about both the proximate and ultimate causes of extra-pair mating in red-winged blackbirds.
KW - Age
KW - Extra-pair mating
KW - Neighbors
KW - Red-winged blackbird
KW - Synchrony
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U2 - 10.1007/s002650050328
DO - 10.1007/s002650050328
M3 - Article
AN - SCOPUS:0030933926
SN - 0340-5443
VL - 40
SP - 151
EP - 158
JO - Behavioral Ecology and Sociobiology
JF - Behavioral Ecology and Sociobiology
IS - 3
ER -