This year has been a record breaker for Sand Martins and the season is far from over. So far a total of 1798 captures have been made at 2 large colonies on the Lune and a small colony on the Hindburn.
The totals so far are:
New adults 660
New Juvenile 794
Controls: 5
1 from Spain in 2008 (Caught in 2009 on the hindburn)
2 carrying French rings
1 from Sussex
1 unknown
This compares to a total from 2009 of 166 Juveniles and 205 adults.
While a direct comparison in totals is not valid as the weather this year has allowed visits at times when most juveniles are about there is clearly a huge increase in Sand Martin population in the Lune valley this year.
46 birds ringed in 2009 have been recaught this year. This is broken down as follows: 9% of juveniles ringed last year in the Lune valley have been retrapped this year and 15% of adults. On the face of it this is a low survival rate of adults however as the colonies have grown we are not managing to cover 100% of the holes. An additional complication is a new colony has appeared with about 400 holes between the two main colonies on the Lune. A visit is planned to see how many of 2009 ringed birds are breeding there.
A much fully report will appear here at the end of the season.
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