title: Age-related variation in foraging behaviour in the wandering albatross at South Georgia: no evidence for senescence.
abstract: Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates.
authors.affiliation: Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom; British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom.
authors.forename: Hannah
authors.initials: H
authors.lastname: Froy
authors.affiliation: Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Sue
authors.initials: S
authors.lastname: Lewis
authors.affiliation: Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Catry
authors.affiliation: School of Biological Sciences, Bangor University, Bangor, United Kingdom.
authors.forename: Charles M
authors.initials: CM
authors.lastname: Bishop
authors.affiliation: Australian Antarctic Division, University of Tasmania, Kingston, Australia.
authors.forename: Isaac P
authors.initials: IP
authors.lastname: Forster
authors.affiliation: Shizuoka University, Shizuoka, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Fukuda
authors.affiliation: Keio University, Fujisawa, Japan.
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Higuchi
authors.affiliation: Department of Zoology, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Ben
authors.initials: B
authors.lastname: Phalan
authors.affiliation: British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom; Marine and Environmental Sciences Centre, University of Coimbra, Coimbra, Portuga.
authors.forename: Jose C
authors.initials: JC
authors.lastname: Xavier
authors.affiliation: Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Nussey
authors.affiliation: British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Phillips
mesh_terms: D000375:Aging; D000818:Animals; D001522:Behavior, Animal; D001717:Birds; D001947:Breeding; D005260:Female; D040362:Geographic Information Systems; D005845:Georgia; D008297:Male; D012098:Reproduction / Q000502:physiology*