Experts strive to re-introduce Norfolk’s lost species
PUBLISHED: 06:30 04 November 2011 | UPDATED: 09:32 04 November 2011
Scientists and conservation groups gathered in Norwich to debate the difficulties, controversies and recent successes of returning native species to their long-lost habitats.
The increasing practice of species re-introduction was the focus of the Norfolk Biodiversity Partnership’s (NBP) tenth annual conference at the Abbey Conference Centre in Bracondale yesterday.
About 120 delegates joined the forum, including partners from groups like Natural England, the Broads Authority, Norfolk Wildlife Trust, RSPB, and district and county councils.
Regional re-introduction projects have recently brought pool frogs – once extinct in the UK – back to Breckland, and created a protective “ark” to shield north Norfolk’s native white-clawed crayfish from invading rivals.
Such schemes are seen as a way of helping a species adapt to climate change through “assisted migration”, and in some areas can help stimulate tourism and the local economy.
But the forum was told they could also be costly and controversial, sometimes prompting criticisms of “meddling” with nature or providing a “quick fix” which ignores more fundamental problems of habitat decline.
NBP co-ordinator Dr Scott Perkin said: “There is something about species re-introduction projects which captures people’s imagination. Perhaps it is the sense of being able to turn back the clock and repair some of the damage that we have done to the natural world.”
John Buckley, of Amphibian and Reptile Conservation, explained the progress of a project to re-establish Norfolk’s population of pool frogs, a species which died out in the UK in 1993.
Through painstaking archaeological research and genetic analysis, his team found pool frogs in Sweden were the closest relative to the British variety, and collected about 70 specimens to pack up for a flight back to the UK.
The exact location in Breckland was kept secret to guard the amphibians against disturbance from curious wildlife-lovers, or theft by unscrupulous collectors.
The frogs – along with their habitats and predators like the grass snake – are monitored every year and, after several subsequent additions from Scandinavia, the adult population is now estimated to be about 50.
Although the colony has re-established itself, Mr Buckley conceded it was “not as big as he would like to be”.
Mike Sutton-Croft, co-ordinator for the Norfolk Non-native Species Initiative, told the conference about the creation of Norfolk’s first crayfish “ark”.
Three weeks ago about 300 white-clawed crayfish – Britain’s only native freshwater variety – were carefully relocated from the River Glaven to an undisclosed location in north Norfolk. Mr Sutton-Croft said the reclusive creatures are under threat from a larger and more aggressive American invader, the signal crayfish.
“Over the last five or 10 years there has been a move from trying to prevent the spread of non-native crayfish to more proactively creating these “ark” sites for the native crayfish in gravel pit lakes or isolated river catchments,” he said.
“That means establishing a population away from all these threats, where they can live and breed naturally. It is also a bit of an insurance policy so if we lose all our river populations we still have a few sites where we can take them from.”