Our ringing of blue tits to date suggests that they are on track for an excellent season. Despite a rather low breeding population in our nest boxes following two years of poor productivity the numbers of fledged young was high.
Ringing since then has recorded a high population suggesting good survival . Leighton Moss is typical with 369 caught to date 77 up on the whole of 2008. There is still two and a half months yet to go in which we normally catch many birds. Another pointer to productivity is the percentage of adult birds in the catch. In 2008 it was 21% this year it is only 7% the best since 2006.
Blue tits are normally quite sedentary but in years of high population they often irrupt with birds moving some distance. A pointer that this may happen this year is an adult bird ringed at Heysham on 8/10 and caught six days later at Leighton Moss, a movement of 17 kms in just five days. Not exactly in the same league as our true migrants but still unusual for a blue tit.
At the late September meeting of Lancaster and District BWS most members reported no unusual numbers of Blue Tits at their garden feeders. However all the signs are that there is a large amount of natural food available with a good beech mast and berry crop.
John Wilson
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