Between 1987 and 1996 the numbers of badgers Meles meles in Wytham Woods rose from 60 to 228 adults. The area occupied by the population has not changed and thus density has also risen from 10 adult badgers/km2 to 38/km2. This rise parallels an increase in badger abundance seen across Britain in recent years. The hypothesis that this increase is either the consequence of improved badger protection or of changes in habitat can be rejected for this site. Instead, a link between increasing numbers and changing weather patterns, possibly resulting from climate change, is investigated. In particular, attention is drawn to a correlation between mild winters and heavier body weights of badgers in January. Furthermore socio-spatial restructuring within the population may be the mechanism that has permitted high density to be sustainable. The increase in badger numbers at Wytham has not affected population sex ratio, which has remained relatively constant at parity throughout the study.