There are no accurate statistics available on the current badger population in Ireland. However, based on the results of the Four Area project, the best estimate available to my Department is that there are approximately 80,000 to 90,000 badgers in the country.
There is considerable peer reviewed research showing that the removal of badgers results in a reduction in the incidence of the disease in cattle. In Ireland, the first major research project took place in East Offaly between 1989 and 1995. This study demonstrated that, following the removal of badgers, the risk of herd breakdowns in the removal area was significantly reduced, the risk of a TB breakdown in a herd being 14 times higher in the control area compared with the removal area. The next significant study, known as the Four Area Project, was conducted from 1997 to 2002 in four different areas of the country. This project demonstrated that the total number of herd restrictions in the removal areas during the study period was almost 60% lower than in the pre study period. A further study showed that targeted badger removal in County Laois between 1989 and 2005 had a significant beneficial impact on the risk of future breakdowns.
The UK has also conducted significant research into the role of badgers in the spread of TB and the impact of the removal of badgers on the incidence of TB in cattle. The most recent research was conducted by the Independent Scientific Group, which directed the Radomised Badger Culling Trial (RCBT). The initial findings of the trial showed a 19% reduction in the incidence of TB in cattle in the removal areas but a 29% increase in the areas surrounding the removal area. However, the effects of the cull continued to be monitored after the cessation of culling and a recent report by DEFRA concluded that, overall, from the beginning of the cull, there was a 28% reduction in TB confirmed cattle herd incidence in the culled areas when compared with the survey-only areas. In addition, confirmed TB herd incidence on the land 2 km outside the culling area was comparable with that in the survey-only areas.
I am satisfied that the badger culling strategy, which is an important element of my Department’s Bovine TB eradication programme, has contributed to a significant reduction in the incidence of bovine tuberculosis here. Since 2000, the number of reactors has declined from 40,000 to 18,500, the lowest recorded since the commencement of the eradication programme in the 1950’s. It is interesting to note that the incidence of TB in Great Britain, which does not implement a badger removal programme, has increased substantially from 6,000 reactors in 1999 to 33,000 in 2010. I understand, however, that DEFRA intends to implement a pilot badger cull in the Autumn.
My Department intends over the coming years to gradually replace badger culling with badger vaccination and, with this in mind, we have been funding research in UCD and collaborating with DEFRA in the UK on research into a vaccine to control tuberculosis in badgers. Research to date has demonstrated that oral vaccination of badgers in a captive environment with the BCG vaccine generates high levels of protective immunity against challenge with bovine TB. However, field trials are also being undertaken to assess the impact of the vaccine on the incidence of disease in field conditions. If these trials are successful, badger vaccination will be incorporated into the eradication programme. However, it will be some years before the trials are completed and therefore targeted badger removals will continue in the medium term.
Maureen O'Sullivan T.D.
Independent Dublin Central