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Mate Fidelity (mate + fidelity)
Selected AbstractsAdult survival, dispersal and mate fidelity in the White-fronted Plover Charadrius marginatusIBIS, Issue 1 2008PENN LLOYD First page of article [source] Pair bond and breeding success in Blue Tits Parus caeruleus and Great Tits Parus majorIBIS, Issue 1 2005MIRIAM PAMPUS Data from 939 nests of the Blue Tit Parus caeruleus and 1008 nests of the Great Tit P. major from nestboxes provided in superabundance in mixed forest study sites between 1976 and 2001 were analysed to examine the effects of mate retention on breeding success and the relationship between mate fidelity and site fidelity. Most birds retained their former partner (76% in Great Tits and 65% in Blue Tits). The probability of a pair divorcing was affected by male age in Great Tits, divorce being more likely in pairs with first-year males. Great Tit pairs breeding together for a second season bred earlier, but had no higher breeding success than pairs breeding together for the first time. In Blue Tits laying date and start of incubation tended to be earlier in pairs breeding together for a second season, but hatching and fledging dates were not earlier than in other pairs. Great Tit pairs breeding together for two consecutive seasons bred earlier in the second season than in the first, but breeding success did not differ significantly between years. In both species, breeding performance did not differ between pairs that divorced after a season and pairs that stayed together. Thus breeding success did not determine whether a pair divorced or bred together again. Neither Blue Tits nor Great Tits improved their breeding performance through divorce. Blue Tit females even had fewer fledglings in the year after divorce than in the year before. Mate retention affected breeding site fidelity. Blue Tit females had greater breeding dispersal distances between consecutive years when re-mating than when breeding again with the same mate. In Great Tits both males and females dispersed more when re-mating than when retaining the former partner, suggesting that mate retention increased the chance of retaining the breeding site. In both species, breeding dispersal distances did not differ between pairs that divorced and pairs in which one mate disappeared. Because no major advantage of mate retention was evident, we suggest that mate retention evolved under different conditions than those found in study sites with high breeding densities and a superabundance of artificial nesting sites. [source] Effects of age, breeding experience, mate fidelity and site fidelity on breeding performance in a declining population of Cassin's aukletsJOURNAL OF ANIMAL ECOLOGY, Issue 6 2001Peter Pyle Summary 1We examined how mate and site fidelity varied with age, experience and sex, and how age, breeding experience, mate experience, site experience and sex affected annual reproductive success and lifetime reproductive output in a declining population of Cassin's auklets (Ptychoramphusaleuticus). Our 276 study birds were 2,14 years of age, recruited at age 2,12 years, and had 0,11 years' breeding experience, 0,8 years' experience with the same mate and 0,11 years' experience in the same nest box. 2Mate fidelity was significantly greater with increasing age in males but not females. There was also a significant negative relationship between mate fidelity and breeding density (as measured by proportion of box occupancy); i.e. the lower the breeding density the higher the incidence of breeding with the same mate. 3Site fidelity showed significant linear and curvilinear increases with age that were significant in females but not males. There was also a significant negative relationship between site fidelity and breeding density; i.e. the lower the breeding density the higher the incidence of breeding at the same site. 4Previous breeding experience had no effect on either mate fidelity or site fidelity, and both mate and site fidelity were significantly lower after a breeding season was skipped. In addition, mate fidelity was significantly lower when a site was switched and vice versa. 5Lifetime reproductive output increased significantly with mate fidelity but showed no relationship with site fidelity. This suggests that fitness is optimized more through mate selection than site selection and that mate fidelity is not a by-product of site fidelity. 6Annual reproductive success showed a significant linear increase with age in males but not females, and a strong parabolic relationship with breeding experience that was significant in both sexes and significantly greater in males than females. 7These results suggest that (i) males may be more responsible for mate selection and females for site selection; (ii) improved foraging experience with age and a cost of reproduction may be more important factors in males than females; and (iii) reproductive success may be optimized by behaviour of the male rather than the female. 8Controlling for the age and experience terms of both parents, experience with a mate had a significant positive linear effect on annual reproductive success. This suggests that mate fidelity is adaptive in Cassin's auklets, and that studies examining the effects of age and experience on reproductive performance should separately consider the duration of the pair bond. 9,Controlling for all other variables, neither experience at a breeding site nor breeding density showed significant correlations with reproductive success. 10,We suggest that reductions in food supply, which correlate with reduced breeding densities, may prevent all but the highest quality breeders (those which have already established a pair bond) from reproducing, and that the increase in quality offsets the reduction in food availability. [source] Parental care and social mating system in the Lesser Spotted Woodpecker Dendrocopos minorJOURNAL OF AVIAN BIOLOGY, Issue 4 2000Ulf Wiktander The sexes' share in parental care and the social mating system in a marked population of the single-brooded Lesser Spotted Woodpecker Dendrocopos minor were studied in 17 woodpecker territories in southern Sweden during 10 years. The birds showed a very strong mate fidelity between years; the divorce rate was 3.4%. In monogamous pairs, the male provided more parental care than the female. The male did most of the nest building and all incubation and brooding at night. Daytime incubation and brooding were shared equally by the sexes, and biparental care at these early breeding stages is probably necessary for successful breeding. In 42% of the nests, however, though still alive the female deserted the brood the last week of the nestling period, whereas the male invariably fed until fledging and fully compensated for the absent female. Post-fledging care could not be quantified, but was likely shared by both parents. Females who ceased feeding at the late nestling stage resumed care after fledging. We argue that the high premium on breeding with the same mate for consecutive years and the overall lower survival of females have shaped this male-biased organisation of parental care. In the six years with best data, most social matings were monogamous, but 8.5% of the females (N=59) exhibited simultaneous multi-nest (classical) polyandry and 2.9% of the males (N=68) exhibited multi-nest polygyny. Polyandrous females raised 39% more young than monogamous pairs. These females invested equal amounts of parental care at all their nests, but their investment at each nest was lower than that of monogamous females. The polyandrously mated males fully compensated for this lower female investment. Polygynous males invested mainly in their primary nest and appeared to be less successful than polyandrous females. Polyandry and polygyny occurred only when the population sex ratio was biased, and due to strong intra-sexual competition this is likely a prerequisite for polygamous mating in Lesser Spotted Woodpeckers. [source] Body size and determinants of laying date variation in the Snow Petrel Pagodroma niveaJOURNAL OF AVIAN BIOLOGY, Issue 3 2000Christophe Barbraud We studied several determinants of laying date variation and the relationship between laying date and reproductive success in the Snow Petrel Pagodroma nivea. The effects of female body size and condition, year, individual laying period, colony size, mate fidelity, previous reproductive success, and duration of the pre-laying exodus on laying date, were investigated during a 3-year study. The average laying date was 4 December. The laying period was compressed into 10,16 days and was very constant from year to year, both for the population as a whole and for individual females. The laying period of individual females varied from year to year on average by less than one day. Body size explained 24% of the variation in laying dates, with large females laying their egg later than small ones. Laying in large colonies occurred c. 2 days later than in small colonies, mainly because a higher proportion of large females bred in large colonies. There was no effect of mate fidelity, age, body condition and previous reproductive success on laying date, but the duration of the pre-laying exodus was strongly correlated with laying date. Smaller females had shorter pre-laying exodus (c. 17.7 days) than larger ones (c. 20.4 days). During the three years of the study reproductive success either increased, decreased or did not vary with laying date. Although body size is not maintained by selection on laying date alone, the genetic body size component of this species suggests that balancing selection on body size may act through laying date. [source] | ||||||||||