As a scientific journal, we are in the business of independently assessing the rigour of work conducted by the research community, including the methods it uses to collect, analyse and interpret appropriate data. We are therefore well placed to judge the merits of relevant scientific endeavour and to provide constructive feedback. On October 30th 2014, the UK’s Shadow Farming Minister, Huw Irranca-Davies, called for an independent review of the methods being used to assess the outcomes of the ongoing pilot badger culls in England 1. Such a review requires a detailed understanding of the behaviour, dynamics and management of wild animal populations – disciplines that are at the heart of the field of animal ecology. As the UK’s leading animal ecology journal, we hereby offer our services to the Secretary of State to provide an independent assessment of the methods and data collected as part of this year’s badger cull.
Badgers and bovine TB
Bovine tuberculosis (bTB) is a terrible problem for Britain’s cattle farmers, costing an estimated £100m in 2013 alone and resulting in the slaughter of more than 32,000 cattle. Unfortunately, bTB control is hampered by persistent infection in populations of wild badgers, which can transmit infection to cattle 2. The challenges of controlling this disease have been identified repeatedly in this and other British Ecological Society journals 3-6, and these peer-reviewed publications provide some of the evidence-base for making decisions about the potential contribution of badger culling to control bTB.
A programme of pilot badger culls began in 2013, and shortly ministers from the UK Department of Environment, Food and Rural Affairs (Defra) will decide whether to expand badger culling to other bTB-affected parts of England. Their decision will rest partly on the estimated level of reduction in badger numbers achieved by the 2013 and 2014 pilot culls. Evaluating such culling effectiveness is important because killing too few badgers has been found to increase bTB in cattle rather than reduce it 7-8. In line with this scientific evidence, Defra’s policy requires that each annual cull should reduce badger density by at least 70% 9.
As most animal ecologists will know, estimating the density reduction achieved by culling is technically challenging and this is especially true for badgers due to them being nocturnal and burrow-dwelling. On the advice of an Independent Expert Panel (IEP), which included our senior editor Tim Coulson, in 2013 both the numbers of badgers and the proportion culled were estimated using molecular methods to identify individual badgers from hair snagged in barbed wire traps 10. However, in 2014 Defra dispensed with both the IEP and the molecular methods it recommended. Instead, Defra plans to estimate badger density reduction internally, using information from culling companies on their culling effort, and the numbers and locations of badger kills 9. Precise details of the planned methods have not yet been made public.
Why is this important?
The implications of these estimates of culling effectiveness are of great interest to policymakers, farmers, wildlife groups, and the general public. This interest is justified because the density reduction achieved by badger culling determines whether this approach will improve or worsen the prospects for bTB control. Due to a lack of transparency concerning the assessment of the 2014 pilot culls, significant concerns have been raised about the methods being used and their utility in assessing the impact of the pilot culls 11,12.
An offer from the Journal of Animal Ecology
In response to recent calls for an independent review of the methods being used to assess the outcomes of the 2014 pilot badger culls, and in the absence of an IEP, we offer Defra the services of Journal of Animal Ecology editors and reviewers to critically appraise the methods used and their power to determine the success of this year’s cull. Should Defra accept our offer, we would provide a transparent and independent review of the available evidence using our extensive international network of reviewers, comprising scientists with acknowledged expertise in wildlife population monitoring and management, as well as expert statisticians and modellers. The Senior Editors of the Journal would personally handle the reviewing process and draw on their team of highly-skilled Associate Editors and external reviewers. To ensure complete independence and transparency, we would avoid calling on scientists that have previously played a part in the contentious badger culling debate, including Tim Coulson, and all reviewers will be identified. In addition, and in line with Journal policy, all relevant data will be archived in a Data repository, such as Dryad or Figshare, where it will be made securely available to the wider stakeholder community. We look forward to hearing from you.
Professor Ken Wilson
Professor Jean-Michel Gaillard
Professor Ben Sheldon
(Senior Editors, Journal of Animal Ecology)
- Hansard (2014). Badger Cull. Commons Hansard 30 Oct 2014, Column 382. http://www.publications.parliament.uk/pa/cm201415/cmhansrd/cm141030/debtext/141030-0001.htm
- Donnelly, C. A. et al. (2006) Positive and negative effects of widespread badger culling on cattle tuberculosis. Nature 439: 843-846.
- Vicente, J. et al. (2007) Social organization and movement influence the incidence of bovine tuberculosis in an undisturbed high-density badger Meles meles population Journal of Animal Ecology 76: 348-360.
- Hone, J. & Donnelly, C.A. (2008) Evaluating evidence of association of bovine tuberculosis in cattle and badgers. Journal of Applied Ecology 46: 1660-1666.
- Bohm, M. et al. (2008) Dynamic interactions among badgers: implications for sociality and disease transmission. Journal of Animal Ecology 77: 735-745.
- Woodroffe, R. et al. (2009) Social group size affects Mycobacterium bovis infection in European badgers (Meles meles). Journal of Animal Ecology 78: 818-827.
- Donnelly, C. A. et al. (2003) Impact of localized badger culling on TB incidence in British cattle. Nature 426: 834-837.
- Woodroffe, R. et al. (2008) Effects of culling on badger abundance: implications for tuberculosis control. Journal of Zoology 274: 28-37.
- Defra (2014). Setting the minimum and maximum numbers for Year 2 of the badger culls: advice to Natural England. (http://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf )
- Independent Expert Panel (2014). Pilot badger culls in Somerset and Gloucestershire – Report by the Independent Expert Panel. (https://www.gov.uk/government/publications/pilot-badger-culls-in-somerset-and-gloucestershire-report-by-the-independent-expert-panel).
- Woodroffe, R. (2014) British government on the badger cull: ask scientists for help then ignore them. (https://theconversation.com/british-government-on-the-badger-cull-ask-scientists-for-help-then-ignore-them-31435).
- Coulson, T. (2014) Name: UK government. Animal ecology test score: 0. (https://journalofanimalecology.wordpress.com/2014/06/23/name-uk-government-animal-ecology-test-score-0/).