Data from: Food availability modulates differences in parental effort between dispersing and philopatric birds
Data files
Jan 19, 2017 version files 242.32 KB
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dataset adults 2014.csv
27.53 KB
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dataset adults from control nests 2012-2013-2014.csv
25.85 KB
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dataset nestlings 2014.csv
73.56 KB
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dataset nestlings from control nests 2012-2013-2014.csv
94.72 KB
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README_for_dataset adults 2014.txt
5.17 KB
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README_for_dataset adults from control nests 2012-2013-2014.txt
5.17 KB
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README_for_dataset nestlings 2014.txt
5.17 KB
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README_for_dataset nestlings from control nests 2012-2013-2014.txt
5.17 KB
Abstract
Dispersal entails costs and might have to be traded off against other life-history traits. Dispersing and philopatric individuals may thus exhibit alternative life-history strategies. Importantly, these differences could also partly be modulated by environmental variation. Our previous results in a patchy population of a small passerine, the collared flycatcher, suggest that, as breeding density, a proxy of habitat quality, decreases, dispersing individuals invest less in reproduction but maintain a stable oxidative balance, whereas philopatric individuals maintain a high reproductive investment at the expense of increased oxidative stress. In this study, we aimed at experimentally testing whether these observed differences between dispersing and philopatric individuals across a habitat quality gradient were due to food availability, a major component of habitat quality in this system. We provided additional food for the parents to use during the nestling rearing period and we measured subsequent parental reproductive effort (through provisioning rate, adult body mass, and plasmatic markers of oxidative balance) and reproductive output. Density-dependent differences between dispersing and philopatric parents in body mass and fledging success were observed in control nests but not in supplemented nests. However, density-dependent differences in oxidative state were not altered by the supplementation. Altogether, our results support our hypothesis that food availability is responsible for some of the density-dependent differences observed in our population between dispersing and philopatric individuals but other mechanisms are also at play. Our study further emphasizes the need to account for environmental variation when studying the association between dispersal and other traits.