Age, sex, and condition as predictors of moult and the efficacy of a novel fur-clip technique for individual marking of the European badger (Meles meles)
Stewart PD., Macdonald DW.
The European badger (Meles meles) moults once a year. In our study site in lowland England, pelage replacement of the guard hairs and a protracted period of fur growth (follicular anagen) occur between May and early November, with a peak in July. The precise timing of the moult depends on the age and condition of the badger Yearling badgers undergo moult significantly earlier than adults. Adult females that have lactated, moult significantly later than other classes of adult, delaying the moult until autumn which corresponds to an annual period of food abundance. Lactation was significantly associated with poor condition in these badgers. It was not possible to determine whether delayed moult was due to poor condition per se, or due to some other physiological consequence of lactation, e.g. hormonal changes. We hypothesize that delay of moult in lactating/poor condition individuals has the adaptive consequence of delaying the metabolic costs of pelage replacement from a tithe of energy deficit until a time of relative plenty. These findings are of practical importance to a novel solution to the problem of individually marking badgers during observational studies. The technique involves clipping the dark band near the tips of the badger's guard hairs to reveal the white under-fur and produce patterning of the coat. The highly contrasting marks were well suited to visual identification during observations under low light and infra-red illumination, and they allowed a large number of individuals (over 80 in our study) to be distinctively marked. The mark persists until the badger undergoes its single annual moult, or until three months of the active phase of fur growth have passed. Clip marks on adults made in late August had the greatest longevity, with 80% still visible after nine months. Though clipping had no significant effect on body condition in our study site, it should be cautiously applied with individuals in poor condition or in cold climates.