Wednesday 23 October 2019

Sand Martins 2019

On the 20th of June I was joined by Nathan for the first visit to the Grangemore Sand Martin colony. I had been keeping an eye on it earlier in the year and had noticed 100+ Sand Martins and lots of fresh holes. We arrived bright and early and got the nets up but the result was disastrous with just three new birds caught and two retraps from previous years one from 22/07/2017 & the other from 14/07/2018. With first catches normally ranging from 56-147 birds, it was looking like a poor year. A new Sedge Warbler, a retrap from July 2017 and a new Meadow Pipit were also caught.

Sand Martin (old picture)

A few more visual visits were made to the site and there were still far too few birds around to warrant any further ringing visits. It is presumed that mammalian predation may have led to the abandonment of the colony - Fox or Badger most likely.

Something that may go in some way to explain where they have all disappeared to is that two of our birds are now breeding in Scotland. The first of these is one of last years juveniles that has opted for a sand quarry in Argyll and Bute, Scotland, 7 kilometres from Campbelltown. The bird was recaptured in Scotland on the 21st of June, 342 days after originally being ringed. The distance between the sites is only 73km but this bird will have migrated to Arica and back in between.

The second bird was also one of our 2018 juveniles and it has moved even further north. It was captured on the 28th of June along the River Lochy to the north-east of Fort William, Highland, Scotland. This site is 218 kilometres to the north east of us, 349 days between ringing and recapture.

Sand Martins have also recolonised the southern side of the Portstewart Strand spit tip and a few have taken up home in Castlerock Golf Club, so, although our main bank is down, they are still doing well in the estuary - but certainly lower numbers.

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