Lower cull targets are easier to achieve but risk increasing instances of TB in cattle rather than reducing them, warns expert
Wednesday 29 March 2017 10.06 BST Last modified on Wednesday 29 March 2017 17.40 BST
The government’s killing targets for the controversial badger cull in England are “deliberately being biased down”, according to a leading animal population expert.
The badger cull, now rolled out to seven counties in England, is part of efforts to reduce the scourge of tuberculosis in cattle but has been heavily criticised by scientists.
Farmers failed to meet the targets for badgers shot in the first culls and the lower targets have been easier to achieve. But scientists warn that lower targets run the risk of actually increasing TB in cattle, because the remaining badgers roam more widely and can spread the disease further afield.
“The targets are being based on poor estimates of [badger] population size and are deliberately being biased downwards,” said Prof Tim Coulson, at the University of Oxford, who was a member of the government’s Independent Expert Panel that scrutinised the first year of culling in 2013 before being disbanded.
This less accurate method produces a population estimate with very wide error bars and, rather than using the central estimate to calculate the cull target, the government is using the very lowest figure at the bottom of the range of uncertainty. This leads to a cull target likely to be much lower than needed to remove a high proportion of the badgers.
“The tools are out there to do this properly,” Coulson said. The “gold standard” method, he said, was to capture and identify badgers and then recapture them to calculate a good estimate of the population before and after culling, but that this was discontinued after the first year of culling: “The reason for that was primarily financial.”
Badger populations are now estimated using sett numbers and other landscape features which Coulson said was not very accurate. Furthermore, the government was setting the killing target at the lowest end of these estimates, he said.