Friday 6 July 2018

Sandwich Terns 2018

The Inch Island (Donegal) Sandwich Tern season has been and gone already and it hasn't quite gone to plan. Signs were looking good following the important habitat work carried out by Ken, Richard B with Lee and Martin from NPWS to clear some of the dense vegetation and fill gaps in gabions. The result was a count of 266 breeding pairs of Sandwich Terns with a total of 404 eggs on the 8th of May. Half the colony was noted to have relocated to the lower shore and away from the raised part of the islet where they normally breed, which was a bit of concern with the possibility of high tides flooding the nests.
Difficult weather and the tides resulted in some chops and changes and cancellations with our planned visits and we ended up with just a single ringing visit. 2018 was to the be the first year of a colour ringing project and we had everything purchased and in place but a miscommunication meant that the colour rings were left behind for the ringing visit.

The ringing visit took place on the 21st June with myself, John, Ken, Gary, Lee and Martin present. On landing on the island it was clear that the storm the week previous had a big impact with lots of dead chicks and dried eggs along the shore, the Black-headed Gulls were particularly affected. It was evident that a number of the Sandwich Terns had fledged with small gatherings at either end of the islet with perhaps 50+ fledged already. We located and ringed a total of 92 chicks in and around the nest sites and managed to catch a further 8 of the semi-fledged birds. There looked to be some more recent nests in a new area and with any luck these eggs will have hatched in the fantastic weather - perhaps too nice!

The Common Terns usually lay a few weeks later than the Sandwich Terns with perhaps 20-25 nests located. All but a couple of nests with 1/2 day old chicks were with eggs and none will be ringed this year. A handful of large Black-headed Gulls were ringed.

Given the reduced catch, only 45 minutes on the islet and the number of large chicks it would have been the perfect opportunity to begin colour ringing. It is a bit of a set back but there is always next year... Metal rings, as they always have done, do still produce recoveries including this bird below which was very slow in coming through but had its ring read in Germany July 2016.

The bird was ringed as a chick on Croaghan Islet in Mulroy Bay, Donegal on the 4th of June 2007 and recovered at Nordfriesisches Wattenmeer Nature Reserve on the 01st July 2016. The nature reserve lies within the Schleswig-Holstein Wadden Sea National Park on North Sea coast of Germnay, a distance of 1039km from Donegal. This bird will have easily travelled 50,000+ kilometres in it's life time. 

Nordfriesisches Wattenmeer Nature Reserve

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