A 36 percent drop in fledgling production was
recorded for Reed Warbler, a species that is vulnerable to flooding of nest
sites. Photo by Michael Kehoe.
Rain stopped play: Atrocious summer weather
affected food sources and breeding
November 2012. The legacy of the atrocious
summer weather on Britain & Ireland's human population is still very much
in evidence, and reports of reductions in invertebrate numbers, from bees to
butterflies have been rife; but how did birds fare? Thanks to British Trust for
Ornithology (BTO) volunteers, who braved the elements throughout the 2012
breeding season to collect the data summarised below, BTO have been able to
construct a very accurate picture of one of the worst breeding seasons on
record.
It wasn't easy being a bird during the spring
and summer of 2012, but then it wasn't easy being a BTO volunteer either, with
rainfall totals in April and June the highest ever recorded. Across Britain
& Ireland, 4,000 survey participants braved the wet, windy conditions to
monitor birds, taking advantage of the infrequent dry spells to monitor
breeding success by visiting nests as part of the Nest Record Scheme (NRS) or
by recording the number of fledged young ringed as part of the Constant Effort
Site (CES) scheme.
Caterpillars in short supply
The latest results from these BTO surveys show that many species struggled to raise young during 2012. "Caterpillars appear to have been in short supply during the cold, wet weather and many of the woodland birds dependent on them had a poor season," noted Carl Barimore, NRS Organiser. "Blue tit, Great tit and Chaffinch fledged 13%, 18% and 58% fewer chicks respectively; this is the lowest productivity recorded for Chaffinch in almost 50 years and the second lowest for Great tit over the same period. Rainfall may have made hunting difficult for raptor and owl species too, and Kestrel breeding success was also significantly lower than average."
The latest results from these BTO surveys show that many species struggled to raise young during 2012. "Caterpillars appear to have been in short supply during the cold, wet weather and many of the woodland birds dependent on them had a poor season," noted Carl Barimore, NRS Organiser. "Blue tit, Great tit and Chaffinch fledged 13%, 18% and 58% fewer chicks respectively; this is the lowest productivity recorded for Chaffinch in almost 50 years and the second lowest for Great tit over the same period. Rainfall may have made hunting difficult for raptor and owl species too, and Kestrel breeding success was also significantly lower than average."
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