2011 has started with sand martins where we left off. We've been catching large numbers of birds at regular colonies on the lune. We still have some new colonies to try and see how many of our birds from last year are using them.
The highlight of the year so far is L334091 which we ringed at Whittington in 2010, was controlled in December in Senegal and then retrapped on Wednesday back at the same colony in Whittington.
Out of the 737 birds caught so far this year 560 have been new birds (256 juveniles, 304 adults), two have been ringed in France, 2 have been controls from the UK. The retraps have been very interesting, the break down of years are below:
2007 - 1, ringed as a juvenile and not seen since ringing
2009 - 10, 8 ringed as adults, 2 as juveniles
2010 - 107, 56 ringed as adults, 51 as juveniles
The 2010 retraps show that the juveniles have so far had a 5% return rate and the adults a 8% return rate. This is significantly lower than last year however the season is yet young and we have more sub colonies to ring at when the wind finally drops.
We have been eagler waiting for details of two French ringed sand martins we caught last year. Sadly the details are yet to arrive from the BTO however in the latest batch of recoveries we have 7 Sand Martins we ringed in 2010 that have been recaught in autumn in France and a further sand martin caught in Shropshire on spring passage. More details of these to follow soon.
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