Thursday, 11 February 2016

Brents Before Breakfast - more successful Brent Goose catches in Dublin


Last week, the Dublin Bay Birds team had the opportunity to do some cannon-netting with the Irish Brent Goose Research Group. As we know from our own cannon-netting work in Dublin, you’re at the whim of the Cannon-net Gods and humour of the birds, so a successful catch is far from guaranteed. But in spite of this wonderfully stormy winter, fickle geese and several over-energetic dogs, we had a few decent catches during the week, in various parks in Coolock, Baldoyle and Malahide.

The geese are fitted with conspicuous colour-rings, which are very easy to see on the geese on the coast, or in many of Dublin’s parks and pitches. The project has been on the go since 2001, and over 3,500 Brent Geese have been colour-ringed in Ireland, Iceland and Arctic Canada to date.

Colour-ringed Brent Goose "JCBY" Ricky Whelan

Unlike our shoreline wader catches, the tide isn’t as important for catches on parks in the city, but it does still play a role. The ideal scenario is to have the net set in luscious grassland close to the coast, when there is high water at dawn. The birds, who have roosted on the water close to the coast, will be hungry after fasting since the previous evening, and, with water levels high, will have to head straight for your luscious grassland for brekkie. That’s the theory anyway, but it doesn’t always work out in practice. And it often means that we have to embark on a @brentgoosechase (follow the lads on Twitter!) to locate the flocks of geese that are flying over our heads into seemingly endless housing estates!
But when things go well and the geese behave, good catches can made and the team have the chance to colour-ring the birds and collect faeces, feather and blood samples and take measurements of each bird.

We had the added bonus of catching 5 Oystercatchers, who were hanging out with the geese in Red Arches in Baldoyle, and we were more than happy to ring them and collect biometric data for our database, which has been somewhat neglected this winter!

Oystercatcher Ricky Whelan

We often read each other’s colour-ringed birds when out on fieldwork, so it’s great to hook up with this well-oiled research machine from time to time and share information on our respective colour-ringed birds. A few of the Brent Geese that we crossed paths with in recent weeks include SKRB who was ringed by the Brent Goose team in his breeding territory in Axel Heiberg in Arctic Canada in 2014. We also connected with DXBY, who has been seen several times in Dublin this winter. It was nice for us to catch up with this lad, as Niall had been part of ringing team to catch and ring this bird in Iceland last May. Another very well recorded bird was also seen recently - 99BB. Having been ringed in 2012, it has been re-sighted in Dublin every year since, in Iceland in 2012 and 2013, and on the Faroe Islands in 2013 and 2014. The value of such a long-term dataset, and the information we can get from such really cannot be overstated.

If you see any colour-ringed Brent Geese, you can find details on how to submit your sightings here.