Artificial supplementary food influences hedgehog occupancy and activity patterns more than predator presence or natural food availability

Supplementary feeding for declining hedgehog (Erinaceus europaeus) populations is popular in Great Britain and has been suggested as an important factor in explaining higher densities in urban areas compared with rural ones. Occupancy modelling was used to test whether spatial variation in supplementary feeding, natural food or predator presence best explained patterns of hedgehog occupancy and activity across a rural urban gradient. Supplementary food had a strong effect on hedgehog occupancy and detection, with all supplementary feeding sites recording hedgehog presence. Sites with supplementary feeding also detected hedgehogs earlier in the evening and had different patterns of diel activity to those sites without. Natural food availability and predators showed a negative relationship with hedgehog occupancy. Natural prey availability and the presence of predators was relatively higher in rural areas and had a negative relationship with hedgehog occupancy. Although the strength of these relationships was weak, they suggest that local hedgehog occupancy and activity behaviour is greatly influenced by access to artificial supplementary feeding in urban areas. This is the first study to show the importance of supplementary feeding as a covariate of hedgehog occupancy in relation to natural food availability and we recommend that future studies quantify supplementary feeding in population and distribution studies of urban mammals.