Dartford warbler (Jill Pakenham/BTO)
Mapping the Warbler's recovery
By Kevin Heathorn
Experts are mapping the population of Dartford warblers to find out why the species has staged such a remarkable recovery in parts of South West England.
One of Devon's largest landowners is taking part in a crucial UK-wide stock take of the bird population.
Clinton Devon Estates is funding research into the Dartford warbler - one of more than 250 species which will feature in the 2007-2011 Bird Atlas, a comprehensive study of bird distribution patterns.
The survey is being organised by the British Trust for Ornithology (BTO), BirdWatch Ireland and the Scottish Ornithologists' Club.
Mapping the bird population will help experts to find out how changes in habitat and climate have affected various species over the last 20 years.
Dartford Warbler (Mike McKavett, RSPB)
In an amazing turnaround in fortunes, the Dartford warbler has staged a remarkable recovery in parts of South West England.
In 1994, there was just one pair of Dartford warblers on Exmoor, but the most recent RSPB survey recorded 115 pairs. The figure reflects a national recovery for the species.
Following severe winters in the 1960s, there were only 11 recorded pairs in the whole of the UK. Now, there are an estimated 3,208 pairs - up from 1,890 pairs in 1994.
The recovery is attributed to milder winters, better heathland management and land restoration.
Clinton Devon Estates owns large tracts of land which is the natural habitat of the Dartford warbler - including Woodbury Common and the East Devon Pebblebed Heaths.
"The Dartford Warbler is an example of a species which was very close to extinction in the 1960s with just a few pairs remaining," explained Jack Varley, estates director of Clinton Devon Estates.
"Now there are estimated to be in excess of 3,000 breeding pairs, but we won't know the true picture until this vital research is complete.
"We have a close affinity to the Dartford Warbler, whose natural habitat is classic lowland heath with gorse and heather, just the sort of environment we are helping to preserve by careful management of our own East Devon Pebblebed Heaths.
East Devon Pebblebed Heath (Clinton Devon Estates)
"Normally, the Dartford Warbler is found much further south, but it seems to like the dense gorse offered by the heaths – as do the Curlews, Yellowhammers, Buzzards and Kestrels."
The study began in November 2007 and will span four winters and four breeding seasons.
It's estimated that more than 50,000 volunteers will be involved in counting and mapping birds during the four year period.
"This national stock take covers all types of bird from the most common to the more endangered," said Andy Clements, director of the BTO.
"Forty of the species on our list are red listed and 121 amber listed as Species of Conservation Concern.
"The work will help us to provide firm scientific evidence on the health or otherwise of the bird population.
"This information can then be used by the BTO, other conservation organisations and the Government to enable us to take the right steps to protect our birds and their habitats in the future."
The study will update research compiled in the Bird Breeding Atlas of 1988-91 and the Bird Wintering Atlas of 1981-84.
last updated: 27/03/2008 at 09:03