0926 GMT August 12, 2022
The otter, polecat and pine marten have bounced back from the brink of extinction, and the country’s only carnivorous mammal now in danger of being wiped out is the wildcat, with the dwindling Scottish populations hit by hybridization with domestic and feral cats, theguardian.com wrote.
Britain’s carnivores have largely ‘done it for themselves’ and recovered often unexpectedly quickly after a reduction in harmful human activities — hunting, trapping and the use of toxic chemicals — according to scientists from Exeter University, Vincent Wildlife Trust and the Centre for Ecology and Hydrology.
But the scientists warn that, while carnivore populations have recovered over the course of a human lifetime, most are still at long-term historical lows, with much more scope for recovery in distribution and density.
“Carnivores have recovered in a way that would have seemed incredibly unlikely in the 1970s, when extinction of some species looked like a real possibility,” said lead author Katie Sainsbury from the Environment and Sustainability Institute at Exeter University.
“Most of these species have essentially recovered by themselves, once pressures from predator controls and pollutants were reduced, and it’s taken them a while. Yes, there are more of them now than in most people’s lifetimes, but that doesn’t mean there isn’t potential for populations to grow and spread further.”
The reasons for each carnivore’s recovery are different. Otters were harmed by organochlorine pesticides washed into rivers but have returned to every English county since the pesticides were banned and hunting was outlawed in 1978. There are now an estimated 11,000.
Polecat numbers have risen to 83,000 in the decades since a 1958 ban on gin traps, which were once used to control rabbits and also widely caught polecats. Polecat populations moved eastwards at about three miles a year between 1975 and 2015, finally returning to the south-east, Midlands and East Anglia.
Badger populations are estimated to have doubled since the 1980s, assisted by a decline in persecution since their legal protection in 1973 and protection of setts in 1992.
Researchers also believe that milder winters caused by climate change are helping badgers survive the season in better shape and raise more cubs.
The population trend for stoats and weasels is also believed to be rising but is less clear: Ironically, the best data comes from gamekeepers who record numbers killed each year.
“Most of these animals declined in the 19th century but they are coming back as a result of legal protection, conservation, removal of pollutants and restoration of habitats,” said Professor Robbie McDonald, the head of Exeter’s Wildlife Science group.
According to McDonald, reintroductions also played a part. The Vincent Wildlife Trust led a successful translocation of pine martens from Scotland to Wales, with 51 Scottish pine martens reinforcing Welsh populations between 2015 and 2017.
Another reintroduction project is set to help this slow-breeding mustelid return to the Forest of Dean. There are estimated to be just 3,700 pine martens in Britain.
D. Jenny Macpherson of Vincent Wildlife Trust said: “People are key to carnivore recovery. By involving local communities from the outset, we have been able to secure the return of healthy numbers of pine martens to Wales. Translocations were needed because natural spread, something the trust has been monitoring in polecats over the past 25 years, will take much longer for the slower-breeding pine marten.”
Future threats to continuing recoveries in carnivore populations include the over-use of rodenticide poisons and new diseases which hit prey. Stoats are very dependent on rabbits, which are declining because of a deadly new rabbit virus, rabbit haemorrhagic disease type 2.
Recent data suggests showed a decline of 45-percent in the number of foxes seen in England from 1996 to 2016, which coincides with the falling rabbit population.
With anglers increasingly vocal about rising otter populations and the potential for small carnivores to trouble gamekeepers, the researchers warn that much will depend on how people devise ways to prevent conflict and allow long-term co-existence as Britain’s carnivores expand their ranges and numbers.