Science aligns against Welsh badger cull

The Welsh Assembly Government was not planning a badger cull in Pembrokeshire as a scientific experiment that would determine whether culling works or not.

It saw the cull as part of a comprehensive plan that would eradicate tuberculosis in the cattle herds of the region, a disease that cost taxpayers £24m in 2008.

Now, following a judgement in the Court of Appeal in London, the cull is on hold - perhaps permanently.

The assembly government says it is considering its options.

And although the Badger Trust says it has a written pledge from the assembly government that it will not appeal, Wales' Chief Veterinary Officer Christianne Glossop told BBC News on exiting the court: "it isn't over".

If the assembly government still intends to go forward, it could appeal to the Supreme Court, or it could construct a new control order that aims to get round the points on which the Court of Appeal made its ruling.

Balance judgement

The Badger Trust appealed on three grounds, which essentially boiled down to these:

• the assembly government did not expect the cull to generate a "substantial" reduction in TB incidence, which is required in law

• it had failed to balance concern for badgers and nature against the projected benefit to farmers

• its control order covered the whole of Wales, but should have been directed only to the North Pembrokeshire target zone.

On the third point, the three judges were unanimous - the assembly government was in error.

The exact location of the proposed cull has not been announced

But the assembly government had conceded as much before the judgement, and was preparing to launch an amended control order within days.

The first two points, which are far more significant, split the judges.

Two agreed with the Badger Trust on both points, while the third agreed with the assembly government.

Lord Justice Stanley Burnton - one of those siding with the Badger Trust - left the door open for Rural Affairs Minister Elin Jones to get round the balance question, simply by presenting a case showing that harm to badgers had been considered when drawing up the control order.

"Had she done so, this ground would have failed," he opined.

However, Ms Jones and Dr Glossop may find it harder to counter the most fundamental argument of all - that badger culling would not make a substantial cut in the incidence of bovine TB.

The scientific study of most use here is the Randomised Badger Culling Trial (RBCT, also known as the Krebs trial) - a vast UK study that saw 11,000 badgers killed in the name of finding out whether culling can be an effective control strategy.

Essentially, the answer was "no".

Reactive culling - killing badgers when there was a TB outbreak - made things worse.

Proactive culling - trying to wipe them out from areas irrespective of TB incidence - made things better inside the cull zone, but worse in a ring just outside.

It's from the balance of the two effects in the proactive arm that the 9% figure arose.

Follow-up research on the Krebs sites is still going on, because finding out how along any effect lasts for is clearly important.

As the years go by, you might expect the effects to subside. But the evidence is not entirely clear.

In February this year, the Krebs team published a scientific paper showing that by July 2009, the benefit of proactive culling appeared to have disappeared.

But by the end of 2009, it had apparently come back.

One of these findings is presumably an anomaly.

But finding out which, and painting the true picture, will take yet more follow-up research; and in the meantime, it is going to be impossible for WAG to argue that culling will produce a more substantial impact than a 9% reduction.

Playing possum

Dr Glossop has spoken approvingly of the experience in New Zealand, whose government is also trying to wipe out bovine TB, largely through a wildlife cull.

But the carrier in New Zealand is not the badger but the possum.

Ecologically, badgers and possums are absolutely not the same. If anyone in the assembly government or any farmers in Wales ever presumed that a New Zealand approach could just be transplanted to Wales, they were wrong scientifically - and, perhaps, ethically.

Introduced from Australia for the fur trade, New Zealand possum numbers soared to about 70 million by the 1980s.

The common brushtailed possum: definitely not a badger

They are culled by lacing carrots with a potent toxin called 1080 and strewing them across the land. Other wildlife are poisoned in the process.

It is a controversial programme, even in a country where some people will happily rig amateur traps for possums and shoot them for fun.

Did Dr Glossop and the assembly government ministers underestimate the level of opposition that might arise when they proposed culling not a pesky alien invader but an iconic native mammal?

Any new control order would have to go through the Welsh Assembly. Given the unrest that has been documented in the prospective cull region and further afield, will assembly members have the political appetite?

That's one way in which the stars appear to be aligning themselves against Elin Jones and the other cull proponents - and against those in the Westminster government who, like Agriculture Minister James Paice, have been itching to get started in England.

As time goes by, the evidence for a sustained effect of culling is likely to weaken. And TB rates in Pembrokeshire would be expected to fall as the other measures taken by the assembly government come into effect, including enhanced biosecurity on farms and additional testing of cattle.

Meanwhile, vaccinating badgers becomes a nearer-term prospect, with trials underway in the Irish Republic and poised to begin in England.

Even the Irish government, which endorsed culling nearly a decade ago, does not see killing badgers as a TB eradication tool. For that, it says, an effective vaccine is needed.

Silent killer

Another question is how North Pembrokeshire farmers will react now.

It is an open secret that silent (and illegal) killing of badgers goes on, and not just in Wales.

It is an understandable reaction from a human point of view. But scientifically, it is just about the worst thing a farmer could do.

"The science says it'll make the problem worse," says Dr Rosie Woodroffe, one of the scientists on the Krebs trial who is now based at the Zoological Society of London.

"Small-scale illegal killing will work like reactive culling and will increase the incidence of cattle TB, as it disrupts badgers' social structure, making them range further afield and transmit the bacterium to more badgers and more cattle."