Brent Goose – 2021-22 WeBS

Branta bernicla – GWYDD DDU – Winter visitor and passage migrant. Not recorded in June or August

Brent geese were occasional visitors to Pembrokeshire before 1990, and only began to appear regularly on WeBS counts in1993-94 as shown below. The Cleddau Estuary is now the sixth-most important site for the species in Wales, with most of the birds being seen in the north of the country. Almost all of the birds seen here are of the light-bellied hrota subspecies of Nearctic origin, for which the threshold for national Importance is 16, so Cleddau estuary qualifies easily.

The highest numbers in any season are recorded between December and February

Almost all brent geese are seen on the Cleddau, especially at the Gann or at Angle Bay.  Just a handful are counted on the Nevern and Teifi.

As the birds commute – either in a flock, or in small groups – between the Gann and Angle Bay – it is possible that they can be double-counted at times.  However, an individual count of 77 at Angle Bay in December 2016, (and other individual counts – 68 at the Gann in 2012 and 62 at Angle Bay in 2017 – on non-WeBS days) suggest that the WeBS totals are reasonable.

Almost all birds are of the light-bellied race (hrota) – with just a handful of dark-bellied birds recorded.

Where do our Brent Geese come from?

Many ringed birds have been observed, and these prove movements between Ireland (main ringing station), Pembrokeshire and Brittany (blue dots on the north-west corner of France on the map below), and to north-east Canada (breeding grounds – red dots for summer sightings) via Iceland and Greenland. The dots to the east and north across Europe show the track of (mainly) dark-bellied Brent geese that are more common on the east and south coast of Britain in winter – although a few (non-ringed) are occasionally seen in Pembrokeshire.

Map from the BTO website, showing more than just the birds seen in Pembrokeshire

These pale-bellied brents are from the ECHA (East Canadian High Arctic) flyway population. They breed very far north in Canada, and overwinter mainly in Ireland, although some birds, like yours, also go to western and southern GB, the Channel Islands and France (mainly Normandy). They stage for a considerable period in spring and autumn in Iceland, and have a hazardous trip over the Greenland Icecap in between. The current flyway population is of the order of 38 – 40,000 birds.  Our current ringing programme commenced in 2001. We ring mainly by canon-netting here in Ireland, and on the spring migration in Iceland in May. Two expeditions have been mounted to catch birds in Canada, in 2007 and 2014. On both occasions, just under 200 birds were caught whilst flightless (herded by helicopter!!). Overall we have now caught just over 4,900 individual geese, so it is well worthwhile checking out any flocks you might come across for leg-rings. Currently, resightings are reaching well over 10,000 records per year from the wintering grounds, and a further 5,000 from Iceland in spring and autumn. Graham McElwaine the Re-sightings Co-ordinator for the Irish Brent Goose Research Group, 2017

Annie Haycock (BBS & WeBS local organiser)

More about the Brent Goose in Pembrokeshire