title: Validating the use of intrinsic markers in body feathers to identify inter-individual differences in non-breeding areas of northern fulmars.
abstract: Many wildlife studies use chemical analyses to explore spatio-temporal variation in diet, migratory patterns and contaminant exposure. Intrinsic markers are particularly valuable for studying non-breeding marine predators, when direct methods of investigation are rarely feasible. However, any inferences regarding foraging ecology are dependent upon the time scale over which tissues such as feathers are formed. In this study, we validate the use of body feathers for studying non-breeding foraging patterns in a pelagic seabird, the northern fulmar. Analysis of carcasses of successfully breeding adult fulmars indicated that body feathers moulted between September and March, whereas analyses of carcasses and activity patterns suggested that wing feather and tail feather moult occurred during more restricted periods (September to October and September to January, respectively). By randomly sampling relevant body feathers, average values for individual birds were shown to be consistent. We also integrated chemical analyses of body feather with geolocation tracking data to demonstrate that analyses of δ13C and δ15N values successfully assigned 88 % of birds to one of two broad wintering regions used by breeding adult fulmars from a Scottish study colony. These data provide strong support for the use of body feathers as a tool for exploring non-breeding foraging patterns and diet in wide-ranging, pelagic seabirds.
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Lighthouse Field Station, Cromarty, IV11 8YJ UK ; British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET UK.
authors.forename: Lucy R
authors.initials: LR
authors.lastname: Quinn
authors.affiliation: Institute for Global Food Security, Queen's University Belfast, 18-30 Malone Road, Belfast, BT9 5BN Northern Ireland, UK.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Meharg
authors.affiliation: IMARES Wageningen UR, PO Box 57, 1780 AB Den Helder, The Netherlands.
authors.forename: Jan A
authors.initials: JA
authors.lastname: van Franeker
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Lighthouse Field Station, Cromarty, IV11 8YJ UK.
authors.forename: Isla M
authors.initials: IM
authors.lastname: Graham
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Lighthouse Field Station, Cromarty, IV11 8YJ UK.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson