Image caption Advisors warned that the cull could breach a European wildlife protection treaty

UK badger culling plans could kill tens of thousands of the animals, worsen the cattle tuberculosis problem, and put the country in breach of a European wildlife treaty, advisers have warned.

The government is to allow culling in England to curb cattle TB, with a similar move possible in Wales.

The Labour Party used Freedom of Information (FoI) laws to obtain advice given by Natural England.

It highlights aspects of ministers' plans that are not backed by science.

Earlier this month, campaigners said they were seeking leave for a judicial review of the government's position.

The Department of Environment, Food and Rural Affairs (Defra) will allow two pilot culls this year in areas of about 150 sq km each, in west Gloucestershire and west Somerset.

If they are judged to be a success, a further 10 areas could be opened for culling each year, up to a maximum of about 40, under licences issued by Natural England.

Better, or worse?

Ministers should listen to the scientists and can this cull Mary Creagh MP, Shadow environment secretary

Defra sees the move as part of a package of bovine TB control measures that will prove beneficial in highly affected areas, alongside restrictions on cattle movements and enhanced biosecurity on farms.

The disease costs the UK public purse about £100m per year.

The Randomised Badger Culling Trial (RBCT), the biggest scientific investigation of culling anywhere in the world, found that it can reduce incidence of TB in farm herds provided it is done in large areas with a large proportion of badgers being killed virtually simultaneously, and that it is sustained for at least four years.

Without this rigour, it found, culling can increase disease spread because it perturbs the badgers, making them roam further and infect new farms.

In the documents obtained by Labour, Natural England warns explicitly that the only badger-culling regime backed by science is that used in the RBCT.

The RBCT ('Krebs') Trial 30 areas of the country selected, each 100 sq km

10 culled proactively, 10 reactively, 10 not culled

Badgers culled through being caught in cage and then shot

Incidence of bovine TB measured on farms inside and outside study areas

Reactive culling suspended early after significant rise in infection

Trial cost £7m per year

More than 11,000 badgers killed

Latest follow-up studies equivocal on whether benefit of proactive culling is maintained

"While it is reasonable to assume that replicating the RBCT approach would deliver similar benefits in a future cull, it is far from certain that these benefits could be delivered via the farmer and landowner-led approach that has been proposed."

In the RBCT, culls were performed by trapping badgers and shooting them, and each area had to be covered within 10 days.

By contrast, the government will allow the much cheaper option of "free-shooting" by trained marksmen across a six-week period, which one former government ecologist has dubbed "a recipe for perturbation".

The FoI documents show that Natural England warned "there is no evidence to support "any approach less onerous than the 10-day window.

Shadow environment secretary Mary Creagh MP said the documents confirmed that Defra had "ignored scientists' advice" on the issue.

"The scientists confirm that the government's cull could spread TB in cattle if farmers fail to oversee an effective cull," she said.

"Ministers should listen to the scientists and cancel this cull which is bad for farmers, bad for taxpayers and bad for wildlife."

A Defra spokesman told BBC News that the government "had taken on board" all responses to its consultation.

"Culling will only take place in the localised areas where it will make a difference, the number of licences to cull badgers will be limited, the licence will specify the maximum number of badgers that can be controlled, and the number of animals controlled will be monitored to guard against local disappearance," he said.

However, the six-week window aspect of the plans was not changed in response to Natural England's submissions, issued in January and July last year.

Prepared for take-up

How popular culling will prove with farmers is unclear. Much is likely to depend on experiences in the two pilot areas.

Image caption Animal welfare groups propose further enhancements to cattle testing, rather than culling

If farmers embrace it enthusiastically, Natural England warns there could be a substantial impact on badger populations.

If 40 areas are eventually licensed and if each has an area of about 350km, it calculates that "the cumulative maximum [badger deaths] that might be reached under the policy is about 90,000 to 130,000 in total".

It continues: "It is unlikely that the survival of the badger nationally would be jeopardised by culling but the local disappearance of the badger in some areas cannot be ruled out if culling is carried out at a large scale."

Killing badgers is generally prohibited under the UK Protection of Badgers Act, with exceptions allowed for disease prevention.

The Badger Trust is already challenging the government on this aspect of its plans, arguing that reducing incidence by 12-16%, as Defra projects, does not constitute "prevention".

Another animal charity, Humane Society International (HSI), is seeking judgement that the government is breaching the EU Bern Convention on protection of wildlife.

Among other things, the convention says that governments "shall prohibit... the use of all means capable of causing local disappearance of, or serious disturbance to, populations of a species..."

HSI's case may be bolstered by the revelation that Natural England specifically warned the government: "If implemented on a large scale... it is our opinion that culling poses a significant risk of contravening Articles 8 and 9 of the Bern Convention".

The government has included in its guidance on issuing licences: "Natural England should aim to ensure that culling will 'not be detrimental to the survival of the population concerned' within the meaning of Article 9 of the Bern Convention".

Last year, wildlife groups began programmes of vaccination, and they believe this will in the end remove any need for culling.

The Welsh government is due to announce its decision on a proposed pilot cull in West Wales early this year.

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