Dataset Details - Grey Seal (Halichoerus grypus) Distribution 2009-2014
Grey seals (Halichoerus grypus)
Data were captured as part of a study on grey seal foraging distribution and fisheries interactions funded under the Beaufort EAF program, National Geographic Global Exploration Fund, National Parks & Wildlife Service and Inland fisheries Ireland
Location data from grey seals captured at haul-out sites in southwest (Blasket Islands n=16) and southeast (Wexford harbour n=14) and tagged with GPS/GSM tags. These tags are glued to the seals fur and last for approximately 6-8 months, they are shed when seal moults. Tags are programmed to capture location (from fastloc GPS) every 30 min and this is succesful if seal is at the surface when at sea. Location and dive data are stored onboard the tag and relayed ashore via GSM network when seal is in GSM range. Approximately 12 at-sea locations are obtained daily for each seal. Tracks are created by linking the 'actual' data points and/or more frequent positions estimation by interpolating the gps data
The terrestrial sites where seals were tagged were limited to southwest (Blasket Islands) and southeast Ireland (Wexford harbour). However seals used waters in Irelands EEZ
Seals were tagged in Feb-March 2009,2011,2012,2013,2014. Tags remained attached (and transmitted) generally for 6-9 months. There are data therefore for all months apart from January, however most data are from March-August
The tags incorporated a hybrid fast acquisition GPS system Fastloc (Wildtrack Telemetry Systems, Leeds) providing up to 12 at-sea positions per day. Accuracy of the Fastloc-GPS locations varies from 724m to 18m depending on the number of satellites used (4 and 6 respectively); the majority of GPS locations used were based on > 5 satellites with approx accuracy of <50m
Complete. Parts of the dataset have been published
Jones et al 2015. Marine Ecology Progress Series 534: 235-249, Cronin et al 2013. Marine Biology 160:531-539, Jessopp et al 2013. PLOS ONE 8, 5: 1-7
Restricted (Data can be viewed on the mapping system but is not available for download)
Michelle Cronin, Grey Seal (Halichoerus grypus) Distribution 2009-2014, National Biodiversity Data Centre, Ireland, accessed 13 October 2019, <https://maps.biodiversityireland.ie/Dataset/227>
Dataset species distribution
Terrestrial Map - 10kmDistribution of the number of species recorded within each 10km grid square (ITM).
Marine Map - 50KmDistribution of the number of species recorded within each 50km grid square (WGS84).
Dataset record distribution
Terrestrial Map - 10kmDistribution of the number of records within each 10km grid square (ITM).
Marine Map - 50KmDistribution of the number of records within each 50km grid square (WGS84).
Records per year
Species per year
|Type of sighting||A description of the type of sighting made|
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