How widespread is the culling?
Culling trials were introduced in the UK in 2013-14 to test ways to control the disease, and culls proper began in 2015.
The cull zones were expanded to a larger area in 2016 and 2017, and in September this year Natural England expanded them again, to areas of the West Country including Cornwall, Devon, Gloucestershire, Somerset, Staffordshire and Cumbria, bringing the total number of zones in England to 32.
The number of badgers culled each year has risen from 615 in 2014 to 19,274 last year.
What preventive measures are in place?
The department of environment and rural affairs (Defra) has policies that include restrictions on movements of TB-affected herds as well as herds that have not been tested by prescribed deadlines. Additionally, all cattle carcasses must be inspected post-slaughter for signs of bTB.
Badger campaigners argue part of the answer lies in tougher biosecurity measures on farms. They believe culls are ineffective because when populations are disrupted, others move into the vacated area, replacing those that have gone, and the movement actually increases the risk of infection.
Experts say the TB skin test, which is the chief method of identifying TB in cattle, is unreliable and that there are more accurate methods, but farmers would have to meet the extra cost.
Is vaccination an option?
Hundreds of volunteers in many affected areas, often supported by Wildlife Trusts, do go out vaccinating badgers, and groups have called on the government to support a nationwide vaccination programme.
Defra says it offers financial support for vaccination projects in certain areas of England, through the badger vaccination grant scheme, and invests in research into an oral badger vaccine, but none is ready to be licensed yet.
“We are also funding major research that could lead to a cattle vaccine becoming available but this depends on overcoming a number of remaining scientific obstacles and completing extensive field trials,” Defra says.
Wildlife campaigners say a cattle vaccine is the long-term solution, but EU rules currently prevent it from being tested and used in the UK so they hope that post-Brexit it could become a reality.
How much does the cull cost?
The cost of culling is met by farmers and the NFU. Defra says it funds the licensing, through Natural England, monitoring and policing.
Earlier this year it was announced farmers would receive £50 for every badger they killed.
The government spent £6.6m on culling last year, and the total cost to date is estimated at about £40m – thought to equal about £1,000 for each animal killed.
Official costs for 2013-17 show that licensing and compliance monitoring costs rose from £859,000 in 2013 to £1.2m last year.
Efficacy monitoring fell from £2.3m in 2013 to zero in the past three years.
Total costs, including advice and equipment, fell from £6.3m in 2013 to £2.5m last year.
In addition to these bills, last year Defra spent £4,046,561 on policing the cull, up from £3,029,998 in 2016.
By contrast, just £175,000 is allocated each year for vaccination.
How effective are the culls?
The evidence is hotly disputed but most experts agree it is inconclusive. The Zoological Society of London says there is no robust evidence that targeting badgers is reducing bovine TB. It is thought the proportion of TB-infected cattle herds is about the same now as in 2013.
However, the number of cows being slaughtered because they are infected is still rising. In 2014, 27,474 were killed prematurely because they tested positively, but in 2017, the figure was more than 42,000.
TB-Free England says that since 2008, 294,428 cattle have been culled in England because of bovine TB.
Nor can dead badgers be used to prove the case either way. Of 994 carcasses tested in 2016, only 4 per cent were shown to have any signs of infection. Wildlife experts say all mammals are susceptible to the disease, and focusing on badgers alone fails to tackle the problem at source.
Analysis of the data for the first three years of culling published last year in the journal Ecology and Evolution showed that reductions in TB incidence were associated with culling in the first two years in Somerset and Gloucestershire. But the authors did not recommend using these findings to develop “generalisable inferences about the effectiveness of the policy at present” because the samples were only small.
A report last year by the Animal and Plant Health Agency which, although again stating the data was limited, concluded: “The unadjusted incidence rate ratios revealed no statistically significant differences between the combined central areas of the intervention areas compared to comparison areas.”
This year the agency stated that “these data alone cannot demonstrate whether the badger control policy is effective in reducing bovine TB in cattle”.
According to Defra’s own latest quarterly statistics, published in September, in England overall, the herd incidence rate – new cases – fell in the 12 months to June 2018 while the herd prevalence rate was almost unchanged.
In Wales, herd incidence and herd prevalence increased slightly on the previous 12 months.
Dr Andrew Robertson, who has a PhD on badger ecology and behaviour and has studied official figures on bTB in badgers, concludes in his blog: “If you look at any of the TB statistics (either in various reports, using the TB dashboard, or using ibTB) you can see that the numbers vary up and down over time and from area to area.
“It is therefore possible that TB could increase or decrease due to other factors which are unrelated to culling. This is clearly demonstrated by the fact that TB trends are often not stable in cull areas in the years prior to culling.
“An updated report/paper using four years of data is currently being prepared by APHA. Until then the data in this recent report may be interesting, but unfortunately they cannot answer the question 'are the culls working?'.”
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