Bovine Tuberculosis (TB) is a terrible illness for animals, causing millions of pounds of losses for the farming industry. In the UK, TB has also been terrible for badgers, which have been mercilessly culled after the British government held them responsible for spreading the disease.
But a new study from the Institute of Zoology has vindicated those who believed the cull to be unsound and unscientific. Badgers and cattle, although they might share the same environment, never come closer than 50 meters (165 feet) from each other on average, according to the study, which means badgers may not be spreading TB to cattle by direct contact.
The team from the Zoological Society of London (ZSL) used GPS collars and proximity-sensing contact collars to understand if and how cows and badgers came into contact across 20 farms in Cornwall. Cattle shared the same environment as the proximity-sensing collared badgers for about 8 years, and the home ranges of GPS-collared badgers for the equivalent of 15 years.
Although this indicates how the badgers and herds occupy the same areas, the team found no evidence of direct interaction. It suggests the transmission of TB between badgers and cattle is not direct, and must be linked to the environment. The results are published in the journal Ecology Letters.
“It has been known for a long time that badgers can transmit TB to cattle – but without knowing how they do it, it is hard to offer farmers advice on the most promising ways to protect their herds,” said Professor Rosie Woodroffe in a statement.
“Our study provides the strongest evidence yet that transmission is happening through the environment, helping to explain why controlling TB is so difficult. This work marks the first step towards identifying more effective ways to reduce transmission between badgers and cattle, and also potentially better ways to manage cattle-to-cattle transmission as well.”
In 2007, it was reported to the government by an Independent Scientific Group that “badger culling can make no meaningful contribution to cattle TB control in Britain.” Against all evidence, the culls have continued yearly, with experts warning that they were disrupting badger setts, encouraging them to disperse more and potential spreading TB to a larger environment.