Effects of extra‐pair paternity and maternity on the provisioning strategies of the Azure‐winged Magpie Cyanopica cyanus

Abstract

Altricial birds show enormous intraspecific diversity in their provisioning strategies, in terms of both the provisioning rate and the amount of food delivered per feeding bout. Extra‐pair copulations (EPCs), which result in either extra‐pair paternity (EPP) or maternity (EPM), provide an opportunity to demonstrate why provisioning strategies vary among individuals. Because EPP‐cuckolded males and EPM‐cuckolded females must raise unrelated young, whereas EPM‐cuckolded males and EPP‐cuckolded females need not, we hypothesized that the first two categories of breeders would reduce parental effort, whereas the latter two categories of breeders would increase parental effort. We tested this hypothesis in the Azure‐winged Magpie Cyanopica cyanus by comparing the number and body mass of fledglings, provisioning rates and food amount delivered per feeding bout between EPP‐ and EPM‐cuckolded breeders and faithful breeders. We found that (1) the number of fledglings did not differ significantly between cuckolded and faithful breeders, and (2) fledglings raised by EPM‐cuckolded males and EPP‐cuckolded females did not differ from faithful breeders, whereas fledglings raised by EPP‐cuckolded males and EPM‐cuckolded females were significantly smaller than those raised by faithful breeders. Compared with faithful breeders, cuckolded breeders increased parental efforts in nests that contained no unrelated young; hence, their loss in parentage may be compensated for by the enhanced quality of fledglings. In nests that contained unrelated young, cuckolded breeders did not reduce parental efforts; hence, their own offspring would not starve and could survive in competition with mixed brood‐mates. Our findings suggest that the differences in parentage created by EPP and EPM scenarios and the potential fitness return of raising a brood for the cuckolded breeders can explain the intraspecific variation in provisioning strategies of altricial birds.

Female preferences for male golden snub-nosed monkeys vary with male age and social context

“…Choices related to male age may also differ depending on the social context. For example, some female song birds choose middle-aged males with territories as social mates, but may also engage in extra-unit copulations with younger males ( Griffith et al 2002 ; Gao et al 2019 ).…”

Males and females of a polygamous songbird respond differently to mating opportunities

“…Extra-pair paternity (EPP) is suggested to be associated with the parental care in Remizidae (Ball et al 2017) and the amount of parental investment in animals in general (Kvarnemo 2018;Gao et al 2020;Schrader et al 2020). However, according to our microsatellite analyses, EPP is relatively low in Chinese penduline tits (around 6%,36 nests,198 nestlings,HW et al unpublished data), which is similar to Cape penduline tits Anthoscopus minutus (5.4%, Ball et al 2017) that obligate biparental care.…”

Coevolution of female fidelity and male help in populations with alternative reproductive tactics

“…Empirical work in birds (e.g. western bluebirds Sialia Mexicana [13], black redstarts [9], scarlet rosefinches Carpodacus erythrinus [14] and azure-winged magpies Cyanopica cyanus [15]), fishes (e.g. the plainfin midshipman Porichthys notatus [16], and the cichlid Variabilichromis moori [7]) and the burying beetle (Nicrophorus vespilloides) [17], however, found that males do not seem to detect cuckoldry or react to it [for instance, in western bluebirds [13], males did not reduce paternal effort even when they observed their mate engaging in extra-pair copulations (EPCs)].…”