Proposals put forward last month could mean the eradication of 70% of the badger population from large areas of the country, yet animal welfare scientists say they could lead to a spread of bovine TB in cattle rather than a reduction.

There are also serious concerns that licensing farmers and/or landowners to free-shoot the animals as suggested would be inhumane and near impossible to monitor.

A public consultation into whether a badger cull in parts of England should make up a package of measures to control bovine TB in cattle was announced by Defra on 15 September. People have been given until 8 December to express their views to the government.

So far nearly 13,500 people have signed our petition to oppose this cull, and a further 6214 have written to their MP to express their views.

The Society is deeply concerned about the proposals and believes they are based on inconsistent evidence. We have therefore sent Defra a list of 38 questions to clarify the detail behind its plans.

It is proposed that groups of farmers or landowners obtain licences to either vaccinate or kill badgers using cage trapping then shooting or the method of 'free-shooting' at night. They are also expected to fund the culling and/or vaccination.

The RSPCA fears that the use of free-shooting would cause serious welfare issues. Badgers' anatomy and behaviour makes them harder to shoot in an accurate, humane way than other animals such as foxes, so the risk of wounding instead of killing them, and causing a painful, slow death, is high.

Defra also says that a cull would have to cover a large area - at least 150km² - and would need to simultaneously target at least 70% of the animals there.

However, scientific evidence* has shown that culling might actually increase the risks of spreading the disease over a wider area - a process called perturbation. Scientists said that a poorly conducted cull using the untested culling methods proposed, which are different to the methods used during a pilot, could increase these risks even further.

Senior RSPCA wildlife scientist Colin Booty said: "The details of how the government proposes to go about this cull are even worse than we imagined.

"They are relying on so many 'ifs' and making assumptions which are not based on evidence.

"Defra wants to use an untested method, free shooting, via untested means, licensed farmers which involves serious risks and could cause great suffering. "Large numbers of badgers could be wiped out, many of them healthy, and it is doubtful whether there would be much reduction in bovine TB in cattle as a result."

The RSPCA agrees that there is a problem with bovine TB but believes a recently-approved TB vaccine for badgers combined with an increased level of cattle testing, improved biosecurity and stricter controls on the movement of cattle, are more sustainable and effective ways of reducing the disease amongst cattle.

The previous government ruled out a cull in 2008 on the basis of science and the responses to its consultation that revealed a record 95% of respondents were opposed to a cull.