This week the second of two pilot badger culls started in Gloucestershire — the first began a week earlier in Somerset.

The government and the National Farmers Union claim that killing badgers is required to control bovine tuberculosis (bTB).

Many independent scientists, naturalists, animal welfare and conservation organisations do not agree.

The pilots are supposed to determine whether cull targets can be met within six weeks and at least 70 per cent of the badger population removed from each cull area.

They are also meant to work out whether shooting free-running badgers at night is a humane way of killing them.

If the pilots are deemed a success the programme will expand with the aim of killing up to 130,000 badgers.

So what are the facts?

Bovine TB is a disease of cattle which can affect a number of other animals, of which badgers are one.

There is no doubting the distress this disease causes farmers or the high cost incurred by culling infected cattle — much of which is borne by the taxpayer.

But there is a serious body of evidence that the badger cull will be ineffective in controlling the disease and that the large sums of money being spent would be better used on other measures such as improving TB testing in cattle, developing better vaccinations for both cattle and badgers and improving biosecurity on farms.

The Randomised Badger Culling Trial, an experiment into badger culling as a preventative measure run between 1998 and 2005, was set by the Department for the Environment, Food and Rural Affairs (Defra) and cost £50 million.

It concluded that “badger culling cannot meaningfully contribute to the future control of cattle TB.”

It also concluded that other approaches to culling were, at best, going to give only slightly better results and, at worst, would have a detrimental effect.

The form this particular cull takes — shooting badgers — could even increase the incidence of TB by encouraging badger movements into neighbouring areas and then back again.

The examples from other countries used by Defra supposedly to show that culls can be successful have been criticised as other factors, such as new movement controls on cattle, could also account for the reported reductions in bTB.

Even setting aside these scientific objections in order for culling to have any hope of “success” enormous areas — at least 150 square kilometres — need to be covered.

The culls have to be sustained in such areas for at least four years and at least 70 per cent of the land must remain accessible.

This is a massive undertaking. Considering that success, as admitted by Defra’s chief vet, would be defined as a reduction in bTB of around 15 per cent — so leaving 85 per cent of the disease untouched — it seems that efforts would be much better directed elsewhere.

There are also real concerns about the methods by which humaneness is being measured in these pilots, one of the key things they are supposed to assess.

Defra has not explained how it is going to collect and analyse the data.

A heavily redacted document was released following pressure from campaigners, which suggested that the noises made by shot badgers would be comparable to those made by harpooned whales.

Nor was any information about how wounded animals that retreat underground to die from infection or starvation would be considered in the humaneness assessment.

The anatomy of the badger means that free shooting carries a very high risk of leaving badgers wounded and in pain.

The Information Commissioner has ruled that Defra was wrong to hide behind Environmental Information Regulations in refusing to disclose further information about humaneness assessments, and the department now has a short period in which to appeal or produce this information.

Finally there is the ethical question of how we treat our indigenous wildlife.

The removal of up to 130,000 badgers will have a dramatic effect on local populations, with badgers possibly cleared from some areas.

Many people are joining peaceful protests in the cull areas, dismayed by the way the government has ignored scientific and ethical concerns.

Campaigners will be watching the results of these pilots closely.

Confidence in Defra to carry out a proper and accurate assessment remains low and the government’s rhetoric suggests it sees wider culling as the answer, regardless of what the pilots reveal.

Continued pressure on the organisations involved to encourage proper consideration of alternative strategies to tackle bTB is vital.

Caroline Allen is a veterinary surgeon and Green Party national spokeswoman on animal issues.