@article{f642baaeec2749739828f86106d78108,
title = "Evidence of age-related improvement in the foraging efficiency of Ad{\'e}lie penguins",
abstract = "Age variation in reproductive performance is well-documented but the mechanisms underlying this variation remain unclear. Foraging efficiency is likely to be a key source of demographic variation as it determines the amount of energy that can be invested in fitness-related activities. Evidence of age-related changes in the foraging efficiency of adult seabirds is scarce and inconsistent. We investigated the effects of age on the foraging efficiency of breeding Ad{\'e}lie penguins, a relatively short-lived seabird species, in order to gain a broader perspective on the processes driving variation in ageing rates. We found support for a positive effect of age, either linear or levelling off at old ages, on both our proxies for daily catch rate and catch per unit effort. Across all age classes, males were more performant foragers than females. We found no strong evidence for differing ageing patterns between sexes or individual quality levels, and no evidence for senescence. We infer that continuous individual improvement could be responsible for a larger amount of the variation in foraging efficiency with age at our study site, compared with selective disappearance of underperforming phenotypes. The different results reported by other studies highlight the need to conduct longitudinal studies across a range of species in different environments.",
author = "Am{\'e}lie Lescro{\"e}l and Grant Ballard and Melanie Massaro and Katie Dugger and Scott Jennings and Annie Pollard and Elizabeth Porzig and Annie Schmidt and Arvind Varsani and David Gr{\'e}millet and David Ainley",
note = "Funding Information: Financial support was provided by NSF grants OPP 9526865, 9814882, 0125608, 0440643 and 0944411. MM was partly funded through a New Zealand Ministry of Science and Innovation grant (C01X1001). DG acknowledges the support of the French Polar Institute IPEV through the program 388 ADACLIM. We thank all fieldworkers at Cape Crozier for their tremendous help in resighting bands since 1997 and Phil O{\textquoteright}B. Lyver (Landcare Research, NZ) for providing accelerometers. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Data were collected using protocols approved by the Oregon State University Institutional Animal Care and Use Committee. This manuscript benefited from reviews by Don Lyons and two anonymous reviewers. This is Point Blue Conservation Science Contribution #2220. Funding Information: All penguin survey, capture and handling methods used for data collection were performed following all relevant guidelines and regulations under the approval and oversight of Oregon State University{\textquoteright}s Institutional Animal Care and Use Committee. Additionally, all work was approved and conducted under Antarctic Conservation Act permits issued by the US National Science Foundation and the U.S. Antarctic Program, and administered by H.T. Harvey & Associates. Publisher Copyright: {\textcopyright} 2019, The Author(s).",
year = "2019",
month = dec,
day = "1",
doi = "10.1038/s41598-019-39814-x",
language = "English (US)",
volume = "9",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
number = "1",
}