Aerial deposition of cadmium has been monitored from 1994-1995 to the present by extraction of cadmium from petroleum jelly coated onto ceramic tiles placed near two nursery roosts and in the foraging area of greater horseshoe bats, Rhinolophus ferrumequinum. The mean cadmium deposit from aerial precipitation recorded in the area from 1994-1995 at locations which were upwind of the power station was 0.11 ± 0.05 mg/kg/mm rain per day compared with 1.01 ± 1.60 mg/kg/mm rain per day at locations downwind. After the oil-fired power station closed in 1996 subsequent analysis from 1998-2000 showed a slight increase in cadmium precipitation at upwind locations (0.22 ± 0.06 mg/kg/mm rain per day) but a decrease at the downwind locations (0.32 ± 0.07 mg/kg/mm rain per day). After closure of the oilfired power station near the bat roosts the aerial deposition of cadmium downwind was reduced but continued monitoring of the cadmium precipitation in the area is indicated since cadmium deposition still occurs. The deposits of cadmium have not had a major impact on the number of adult bats which have increased from 1994 to 2000. The findings made in this study have implications for conservation of the greater horseshoe bats which are at the Northern limit of their distribution.