Badgers: Bovine Tuberculosis

Lord Knight of Weymouth Excerpts

Monday 9th December 2013 Grand Committee

Asked by

[Lord Knight of Weymouth]

To ask Her Majesty’s Government what plans there are in future years to continue with a cull of badgers as part of the Bovine Tuberculosis Eradication Programme, following the withdrawal by Natural England of the licence to cull badgers in Gloucestershire.

[Lord Knight of Weymouth (Lab)]

My Lords, this debate follows the decision by Natural England at the end of last month to prematurely halt the extended licence to cull badgers in Gloucestershire. I believe that this decision indicates that the overwhelming view of the independent scientists on badger culls was correct: that a cull is costly and impractical and that continuing for the remaining years of the licensed cull risks exacerbating the serious problem of TB in cattle.

The problem has been growing over recent decades. I live in the south-west of England, where dairy farmers have been particularly badly hit. It has cost the taxpayer as much as £0.5 billion over the past decade in testing, compensation and research, with further sums borne by the agricultural industry. It therefore follows that urgent action must be taken. There is a logic in thinking that killing badgers should be a part of that. Badgers are undoubtedly involved in transmitting TB to cattle and it therefore seems obvious that fewer diseased badgers will lead to less disease in cattle. However, infection is also passed from cattle to cattle, from cattle to badgers and between badgers. The Government are therefore right to pursue other measures as part of their eradication plan for bovine TB, such as pre- and post-movement testing for cattle.

However, in continuing with culling, the Government ignore the most important part of the science: that the social behaviour of badgers produces a much more unpredictable effect due to the effects of perturbation. I am very happy to stand corrected by the real experts in this debate—the noble Lords, Lord Krebs and Lord Trees—but in layman’s terms, perturbation is brought about by the territorial behaviour of badgers. A group of badgers will stick to a territory around a sett if they detect other badgers at their boundary but will extend their range in the absence of other badgers.

The randomised badger culling trials carried out by the previous Government, devised by the noble Lord, Lord Krebs, who I am delighted to see in his place, had clear and undisputed findings. First, localised small-scale culling of badgers in the RBCT increased bovine TB. Secondly, 100 square-kilometre areas receiving widespread culling had lower cattle TB rates than those with no culling. The benefits took several years to emerge but persisted four years after culling ended. Thirdly, land adjoining the widespread culling areas experienced rapid increases in cattle TB. These detrimental effects faded over time but never turned into benefits. The trials, as with the current pilot culls, tried to reduce these effects using natural impermeable boundaries such as rivers.

These findings informed the current government policy. The licensing criteria are intended to produce large-scale, long-term, rapid and efficient culls, as the trials agreed that small-scale, short-term, slow and inefficient culls will increase cattle TB. By extrapolating the RBCT effects to a 150 square-kilometre circle, it followed that Government-led cage-trapping of badgers could reduce local cattle TB over a nine-year period by 12% to 16% below what it would have been with no culling. However, because background TB levels are rising, this 12% to 16% relative reduction over nine years actually represents a slowing of the rate of increase of cattle TB, not an absolute fall. On average, farmers would probably experience as much TB as they do today, or more. Farmers on adjoining land would almost certainly experience increased TB risks. To get this limited impact, the licence required 80% confidence of culling 70% of the badger population in the area.

When the policy was announced in October 2012, more than 30 of the leading scientists in this area wrote to the Secretary of State. At the very end of their letter, they said:

“Implementing these criteria entails substantial challenges, both for government and for farmers and, as a result, beneficial effects on cattle TB cannot be guaranteed. For example, licensees will be required to cull a minimum number of badgers (to avoid net increases in cattle TB) without exceeding a maximum number (to avoid causing local extinction, which would breach the Bern Convention on the Conservation of European Wildlife and Natural Habitats). Setting such minimum and maximum numbers is technically problematic, especially when local estimates of badger numbers—”

--- Later in debate ---

[Lord Knight of Weymouth]

My Lords, before the Division I was reading an extract from a letter to the Secretary of State from 30 scientists sent in October 2012. I will continue:

“Setting such minimum and maximum numbers is technically problematic, especially when local estimates of badger numbers are very imprecise. Furthermore, shooting the required number of badgers sufficiently rapidly and with due regard to public safety is likely to be challenging in the face of public protest and potentially inclement weather”.

So the Government were warned by the leading scientists.

What do we now know about how the pilots have gone? In Somerset, 65% of the estimated population of badgers was culled in the pilot area. In Gloucestershire, it was just 39%. Based on the science that the Government used to design these pilots, this means that the cull was not sufficiently effective to reduce cattle TB, and in Gloucestershire is likely to have caused more harm than good. Will the Minister therefore tell us when we will get any statement on the record from the Government’s Chief Scientific Adviser, Defra’s chief scientist and the Chief Veterinary Officer, and their analysis of whether the pilot culls have increased or decreased the incidence of bovine TB in Gloucestershire, Somerset and neighbouring areas?

Will the Minister also take this opportunity to explain one other curiosity? The licensing is for trapping and shooting and for free shooting. The data show a sudden increase in the more expensive trapping and shooting halfway through the initial six-week pilot. The extension was stopped at the same time as the cage-shooting season ended, with three more weeks to run for free shooting. This suggests that those carrying out the cull voted with their feet and abandoned free shooting. Is this true? Do the Government expect free shooting to be widespread if they push ahead with a cull over the next few years? Will he publish a new cost-benefit analysis accordingly?

It looks like an effective farmer-led cull is very difficult, due to weather and protesters, as scientists predicted, and due to badgers moving the goal posts, which no one predicted. If an ineffective cull is what we have ended up with, it will make matters worse, so what should we do? The answer appears to be vaccination of badgers. Thanks to FERA trials on the safety of an injected vaccine, we know that it reduces the transmission of the disease among badgers. We do not yet know the effect on cattle, but we could, through the evaluation of vaccination pilots.

The case for piloting vaccination is profound. It plays to the perturbation effect, not against it. Vaccinating an area reduces disease in the badger population in that area while keeping badgers alive. Those badgers then keep out other potentially diseased badgers, thus creating an area where the situation is improving, which also blocks further spread of the disease in badgers.

There are normally three broad arguments against badger vaccination. The first is cost. This objection is because it needs cage-trapping. Given that that is what culling now seems to favour, that element is cost-neutral. Unlike culling, there is negligible policing cost. The pilot culls have cost considerably more to police in Gloucestershire than expected, for example. The remaining element is the cost of the vaccine, offset against the cost of disposing of badger corpses. It is also clear from voluntary vaccination programmes that there is considerable public support. Many come forward to volunteer and some are funding vaccination.

Secondly, people say that we cannot wait for a vaccine to take effect; that it is too slow, with no effect on animals already infected. To that I say: ask the scientists. The annual mortality of badgers is 25% to 35%. Hence, vaccination would work pretty quickly compared to the cull impact of 16% over nine years.

The final argument is that vaccination does not remove infected badgers. The evidence is that, with culling, the reduction in infected badgers is much slower than the overall reduction in the badger population due to perturbation. We know that culling will not reduce the overall level of infection because the overall level of reduction is offset by background levels of rising TB. However, vaccination would at least reduce transmission between badgers without the increase in transmission created by the perturbation effect induced by culling.

To summarise, I am assuming that we mean vaccination by injection; I think there are issues attached to oral vaccine that have to be addressed. There is long-term potential attached to a cattle vaccine, but that is more complex and not something that we can proceed with as quickly as we need to. The Government should look closely at the pilots that they have carried out and then be led by science. This will tell them that culling is impractical, due to perturbation. It may have worked against non-native invasive possums in New Zealand with very different social behaviour, or in Ireland, where much lower badger density leads to much less of a perturbation effect. But the evidence from England is great and consistently shows that it does not work. The efforts and resources spent on culling badgers should be replaced by a vaccination pilot. I look forward to other contributions and to the Minister’s response.