Been a difficult and disapointing month for our Bearded Tit and Reed Warbler RAS study at Leighton Moss. Ringing has proved difficult due to the poor weather but the Bearded Tit population appears to be well down . In June 2014 we caught 65 Bearded Tits of which 54 were juveniles, this year with admittedly less effort we have only caught 7 birds of which only 3 are juveniles.
Reed Warblers are also down, in June last year we caught 115 , this year only 58. Part of the decline is due to the late fledging . We caught the first juveniles(2) this morning 10 days later than in 2014. The highlight of this mornings catch was a Reed Warbler in its 8th year, ringed as a juvenile in 2013 it had not been re-trapped until this morning. It is our 8th oldest Reed Warbler, the oldest was just short of 10 years.
Blue Tits are incidental to our study but they to are well down,34 last year almost all juveniles this year only 5 and not one juvenile. this fits in well with our nest box studies which reveal the lowest productivity since we recorded nest records on IPMR in 2001.
Some of these declines are due to less effort due to poor ringing weather. Last year we netted on 13 occasions compared with 9 this year. But low productivty brought about by the poor spring weather must be the main reason. Lets hope for a more productive July.