DOI: 10.5061/dryad.vb322
title: Data from: State-space modelling of geolocation data reveals sex differences in the use of management areas by breeding northern fulmars

description: Effective management and conservation of terrestrially breeding marine
 predators requires information on connectivity between specific breeding
 sites and at-sea foraging areas. In the north-east Atlantic, efforts to
 monitor and manage the impacts of bycatch or pollution events within
 different Convention for the Protection of the Marine Environment of the
 North-East Atlantic (OSPAR) management regions are currently constrained
 by uncertainty over the origins of seabirds occurring in each area. Whilst
 Global Positioning System (GPS) loggers can now provide high resolution
 data on seabird foraging characteristics, their use is largely restricted
 to the chick-rearing period. Smaller light-based Global Location Sensors
 (geolocators) could provide valuable data during earlier phases of the
 breeding season, but additional information on their accuracy is required
 to assess this potential. We used incubation trip tracking data from 11
 double-tagged (GPS/geolocator) northern fulmars Fulmarus glacialis L.
 within a state-space modelling (SSM) framework to estimate errors around
 geolocator locations. The SSM was then fitted to a larger sample of
 geolocator data from the pre-laying exodus using the mean of these error
 estimates. Geolocator data were first used to compare the trip durations
 of males and females during this critical pre-laying period. Outputs from
 the SSM were then used to characterize their spatial distribution and
 assess the extent of within-colony variation in the use of different OSPAR
 management regions. During the pre-laying exodus, fulmars from a single
 colony in the north-east of the United Kingdom foraged widely across
 several biogeographical regions, up to 2900 km from the colony. Most (60%)
 males remained within the North Sea region, whereas most (68%) females
 flew north, foraging within the Norwegian and Barents Sea. A small subset
 of birds (15%) travelled to the central North Atlantic. Foraging trips by
 males appeared to be shorter (x = 18 days, n = 20) than by females (x = 25
 days, n = 19). Policy implications. Our results of state-space modelling
 of geolocation data collected from northern fulmars show that
 within-colony variation in ranging behaviour during the breeding season
 results in sex differences in exposure to threats such as fisheries
 bycatch and marine plastics. Birds from a single colony dispersed over
 several north-east Atlantic management areas. These patterns have
 implications for interpreting trends in colony-based monitoring schemes,
 and European Union Marine Strategy Framework programmes using these
 seabirds as an indicator species for monitoring trends in marine litter
 and prioritizing efforts to mitigate its impact.
description: Edwards et al., (2016)
 tracking dataGeolocator and GPS data
 used in the double-tagging experiment and pre-laying exodus analysis
 described in Edwards et al., (2016). Data are arranged in folders and
 there is a short readme file associated with the double-tagging
 study.PLE_paper_data.zip