Friday, 15 July 2016


Now that it's July and the brent are hopefully enjoying their breeding season up in High Arctic Canada, it's time to provide a quick update for everyone on some of the early results from the GPS tagged birds (see the blog dated 15 February 2016).
We managed to get GPS downloads from six of these birds in Iceland, which gave us some indication of geese movements during this part of the year, as well as what the birds have been up to since being ringed in Ireland. To give a flavour of the data obtained, Ian Cleasby, from the University of Exeter team, has plotted details of locations for two birds that were downloaded in Iceland, SSRB (in red) and 3LLBO (in yellow). The day and month on which GPS locations were taken are also included in the maps showing the migration between Ireland and Iceland, and the location of ground observations / downloads are shown in white on the maps of Iceland. Thanks to everyone who was involved in this year's fieldwork, from fitting collars to re-sighting and downloading birds in both Ireland and Iceland.


This bird, which was initially ringed during our 2014 expedition to the Canadian breeding grounds, was downloaded on a saltmarsh at Myrar, a vast, relatively undisturbed and inaccessible area on the west coast of Iceland.

After Ringing:

After ringing this bird was recorded mainly from the North Bull area, adjacent to where its collar had been fitted on 08 April 2016.


The GPS data suggest that SSRB began moving north from Dublin on 30 April 2016. By 01 May 2016, it had crossed the north coast of Ireland, reaching Iceland on 02 April 2016.

In Iceland:

When in Iceland, SSRB was recorded as having loitered around Hvalfjordur (Whale Fjord), north of Reykjavik, and east of Akranes, near an immense Aluminium smelter, before moving north to Myrar.


Before the download, 3LLBO had been a bit of a mystery bird. Caught at Malahide on
03 February 2016, it was only re-sighted once from Ireland, the same day, just south at Baldoyle Bay - making where it had been the rest of the winter of particular interest.

After Ringing:

It appears that, at this stage of the winter, Malahide represented the southern limit of 3LLBO's range in Ireland, with most locations being to the north (many at Rogerstown and quite a few from Lambay Island).


3LLBO began moving north much earlier than SSRB, probably on 18/20 April 2016. On the morning of 20 April 2016 there was a GPS fix to the west of the Isle of Lewis, and by nightfall (23:13, to be exact) of the same day, the bird had reached the coast of Iceland

In Iceland:

In Iceland, 3LLBO moved more gradually up the coastline from the greater Reykjavik area, passing Hvalfjordur, where SSRB had been lodged, eventually being seen and downloaded at Blautos, just north-east of Akranes

Condition of GPS Collared Birds

Whilst in Iceland, two GPS collared birds were recaptured, providing a valuable opportunity to examine the physical effect of the collars on the birds. It was found that the collars had caused some abrasion to the birds' neck feathers, wearing off the black tips, resulting in the neck looking a bit greyer.
Initially, whilst watching the GPS birds in Ireland, and receiving comments from other observers on the effect of the collars, there was concern that birds may have been plucking feathers from their necks, exposing down or even skin. However, no evidence was found from either of the recaptured birds that any feathers had been plucked, nor was any down or skin exposed around the collars. More broadly, the collared birds did not appear to have lower API's (a measurement of the bird's weight/condition by abdominal profile) than non-collared birds, and no instances of divorce / family break-up involving collared birds was recorded.