Bearded Tits have had their best season at Leighton Moss since the crash in the population in the 2000/2001 winter. To date we have caught 92 free flying juveniles 41 more than last year. Juvenile survival has been very good- of 16 ringed as nestlings no fewer than 13 have been caught as free flying juveniles. This included 5 out of a brood off 6 ringed in a nest box just 4 m. from a Marsh Harrier nest!. There has also been at least one very late brood, just recently we have caught three in juvenile plumage. A male was caught yesterday and it was just starting to moult and still in full juvenile plumage. So must have been hatched in mid to late August.
The first brood younsters are now very active and showing well. We have been recording fat scores and weight of all the birds we have caught. Recently almost all first brood youngsters have some fat in the trachael pit and they have on the average increased their weight by almost 1.5 grams since August.Is this laying down of fat in preparation for a move?
In some years prior to 2000 some bearded tits have irrupted away from Leighton usually in late October and early November We have had sightings from Marton Mere near Blackpool and birds caught in Bolton, Coventry and three in South Yorshire.
If you do see birds away from Leighton please check for rings as all our birds are colour ringed. (A BTO metal ring and three colours). Please note carefully the position of the colour rings and report them on this site. Many thanks.
John Wilson
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