Craig, Huw, Ian and I 'worked' the Swallow roost again last evening and we had quite a good session. On Saturday evening there had been over a thousand Swallows roosting again but we weren't certain if there would be as many last night. During clear, calm conditions the roost tends to build up as more Swallows are on the move, but as soon as the conditions change leading to less Swallows moving the roost starts to break up. It had been an overcast, breezier and cooler kind of day yesterday and this is why we wondered whether there would be quite as many Swallows roosting. We needn't have worried!
In the end there must have been at least a thousand Swallows roosting with a few Sand Martins mixed in and we ringed 74 birds as follows (recaptures in brackets):
Sand Martin - 5
Swallow - 66
Sedge Warbler - 2
Reed Warbler - 1 (3)
We caught the two old Reed Warblers again and after being 'missing' for some time they aren't any more!
Fingers crossed that the roost will last for a while so we can ring a good few Swallows. What we have found is that as soon as maize on farms is at a similar height to Common Reed in reedbeds the roost will break up. When I first started ringing thirty years ago there was not nearly as much maize grown round here and the Swallows would roost in reedbeds and at this particular reedbed would sometimes have 10,000 Swallows roosting. Happy days!
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