It’s been almost two months since we came to Orkney to deploy GPS tags on harbour seals. The tags, deployed on ten adult seals, have been transmitting information regularly about the movements and dive profiles of each of the seals, showing quite a variety of individual movements around Orkney.
These data enables us to identify the seals’ potential feeding areas, study their diving behavior and movement patterns, and inform us of where the seals haul out. The latest has been very helpful to guide our photo-identification effort around Scapa Flow.
Some seals have been doing relatively short distance trips, like one adult female who has been foraging around Widewall Bay in South Ronaldsay from the start. Others have adventured further. A male that was tagged in Widewall Bay (tag #258) has been crossing the Pentland Firth many times, spending time in Harrow, in mainland. Another male, with tag #260, has explored Scapa Flow, spending quite a lot of time around Flota, and has traveled to the west of Hoy in several foraging trips. Another female took a long trip north past Papa Westray, closely following the coast, before heading back to Widewall Bay.
Here are some examples of the seal tracks (click on each map to enlarge):
The seal that has traveled further so far is a female with tag #256, who was initially tagged in Burray on the 19th of April. She then spent a couple of days around Burray and another few days moving between Flotta, Fara, Hoy and Switha. On April 25th she headed south and followed the coast of mainland until she arrived to the Moray Firth. There, she has been doing foraging trips for over a month, while using the coast between Culbin Sands and Findhorn to haulout. On the 30th May she started heading back north, arriving in Burray on 2nd June, a month and a half after leaving Orkney.
I went out on the 2nd of June to count and take photographs at one of the haulouts, despite the horrible and wet weather. Well, check who I saw having a very well deserved rest… hopefully this female is back in Orkney in time for pupping season.
Our colleagues at the University of Aberdeen Lighthouse Field Station, based in Cromarty, have been conducting harbour seal photo-identification studies in the Moray Firth for many years. It turns out they’ve just had a very similar return story to our traveling female. Two seals that were tagged with GPS back in February 2015, with their last known locations in Orkney and on the north coast, have been recently seen back in Loch Fleet! You can check the details of their travels in their blog.
Written by Monica