Our Birds Did Well In 1995

News from the BTO
18th June 1996

There are several different surveys of Britain's breeding birds organised bye the British Trust for Ornithology. As usual the first with published results for the year is the Constant Effort Sites scheme. This investigation is carried out by bird ringers who set their nets in standard sites 12 times over the period of May to August each year. For 1994 - 1995 115 sites had data which were analyzed by Dawn Balmer and Will Peach.

For the numbers of adult birds caught 1995 was generally very good with significantly higher totals for three migrants - Sedge Warbler, Lesser Whitethroat and Whitethroat. Declines (not significant) were logged for some species where there is concern about long term declines - for example Linnet, Bullfinch and Reed Bunting. Significantly more juveniles were produced in 1995 than in 1994 for seven species - Wren, Sedge Warbler, Whitethroat, Chiffchaff, Blue Tit, Great Tit and Chaffinch. There were few species for which 1995 was worse and for none of them was the change significant.

A very useful measure of productivity is the change in the percentage of juveniles compared with adults ion each of the two paired years, For three species this increased significantly - Whitethroat, Blue Tit and Great Tit. The change for Whitethroats indicates just what a good year 1995 was for this species, possibly better than any other since the population crash almost 30 years ago. For the tits it simply went to make up for a dreadful breeding season in 1994.