although Alan reports a good year at Aughton, the boxes in Roeburndale are having a very poor year. Nesting attempts are higher than previous years, reflecting good productivity and survival from last year, but nest success is much poorer than in previous years.
Many clutches of Blue Tit and Great Tit are smaller than previous years and fewer birds have been hatched than 'normal'. Fledgling survival is poor with many instances of small broods (typically 4 or 5 this year, rather than 8-12 in 'normal' years) and of those fledgelings, many are predated by a number of culprits - possible because young in nests are much more vocal, this year, as if begging ludly for food that parents are finding it hard to find.
Trees in these upland woods were very late in putting out leaves this year (and many trees still do not have complete canopies) so presumably there are fewer caterpillars around? Lowland woods may be faring much better this season than upland woods, although the large nestbox scheme at Lancaster University also seems to be having a poor year.
Migrants, such as Pied Flycatcher appear to have been late arriving, yet have returned in big numbers. Their broods, by being later than the Tit ones, may benefit from the later leaf emergence this year - we wait and see
Paul
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