Wildlife winners and losers of 2017 revealed in BTO BirdTrends report
The winners and losers among Britain’s bird life in 2017 have been outlined in a volunteer-driven study compiled by the Thetford-based British Trust for Ornithology (BTO).
The 20th annual BirdTrends report highlights the rapid decline of the greenfinch, whose population has dropped by 59pc in the UK in just ten years – raising a high-level alert for the first time.
This familiar garden bird was not a conservation concern when the UK’s list was last updated in 2015 but, if numbers continue to fall at the same rate, it could be moved straight to the “red list” of species of greatest concern when it is next updated,
Bird experts say the decline is caused by a widespread and severe outbreak of a disease called trichomonosis, which first affected bird populations in 2006.
The bird is one of 28 species in the report showing “statistically significant population declines” of more than 50pc over long-term periods of 31–48 years.
These are grey partridge, little grebe, lapwing, redshank, woodcock, snipe, turtle dove, cuckoo, little owl, willow tit, marsh tit, skylark, house martin, willow warbler, whitethroat, starling, song thrush, mistle thrush, spotted flycatcher, nightingale, house sparrow, tree sparrow, yellow wagtail, tree pipit, linnet, lesser redpoll, yellowhammer and corn bunting.
The endangered turtle dove shows the steepest decline of any species in the report (98pc) which “suggests it may soon disappear as a British breeding bird”.
However, in contrast to those alarming findings, there are 22 species for which the study’s “most representative long-term trends” show a statistically- significant doubling in population size, over periods of 22–48 years.
These are mute swan, greylag goose, Canada goose, shelduck, mallard, goosander, sparrowhawk, buzzard, coot, stock dove, woodpigeon, collared dove, green woodpecker, great spotted woodpecker, magpie, jackdaw, carrion crow, chiffchaff, blackcap, nuthatch, wren and goldfinch.
One species doing particularly well is the chiffchaff – added to this list for the first time – which is continuing to increase its breeding range and population as it benefits from warmer winters.
Once a very rare sight in winter, the BTO says this small green warbler can increasingly be seen on sunny days in sheltered locations, particularly in milder coastal areas and around inland water bodies.
The BirdTrends report is produced in partnership by the BTO and the Joint Nature Conservation Committee (JNCC), with the data gathered by thousands of volunteer “citizen scientists” across the country.