Performance of fur clips and livestock markers for identifying vaccinated badgers

Abstract

Marking free-living wild mammals may be desirable during field studies and management interventions; however, doing so presents practical challenges. In the context of disease management interventions, different approaches such as vaccination and culling may be deployed in adjacent areas resulting in a need to identify previously vaccinated individuals to avoid losses of vaccination benefits. Badgers (Meles meles) have been identified as a wildlife reservoir of bovine tuberculosis in several countries. In England, the primary means of controlling disease in badger populations has been culling, although policy also includes the use of badger vaccination. Vaccination and culling can therefore increasingly take place in adjacent areas. The current means of marking vaccinated badgers is to apply a fur clip; however, the performance of this method has not been assessed. In this study, we assessed the field performance of livestock markers not previously trialled on badgers. We also assessed the performance of fur clips in terms of (a) how likely they are to be detected on recapture and (b) their detectability using remote cameras. None of the livestock markers trialled persisted well on badger fur. Detectability of fur clips on re-captured badgers fell to 50% in adult badgers by approximately 3 months from application. In cubs, detectability fell to less than 50% within 3 weeks of application. We suggest it is highly likely that, if vaccination and culling were carried out in adjacent areas and fur clipping was the primary means of determining vaccination status, a proportion of recently vaccinated badgers would be removed, particularly cubs. This has important implications for disease control, and we suggest options for minimising such losses.