Predicting hedgehog mortality risks on British roads using habitat suitability modelling
Wright, Patrick et al. (2019), Predicting hedgehog mortality risks on British roads using habitat suitability modelling, Dryad, Dataset, https://doi.org/10.5061/dryad.ksn02v70h
Road vehicle collisions are likely to be an important contributory factor in the decline of the European hedgehog (Erinaceus europaeus) in Britain. Here, a collaborative roadkill dataset collected from multiple projects across Britain was used to assess when, where and why hedgehog roadkill are more likely to occur. Seasonal trends were assessed using a Generalized Additive Model (GAM). There were few casualties in winter — the hibernation season for hedgehogs — with a gradual increase from February that reached a peak in July before declining thereafter. A sequential multi-level Habitat Suitability Modelling (HSM) framework was then used to identify areas showing a high probability of hedgehog roadkill occurrence throughout the entire British road network (~ 400,000 km) based on multi-scale environmental determinants. The HSM predicted that grassland and urban habitat coverage were important in predicting the probability of roadkill at a national scale. Probabilities peaked at approximately 50% urban cover at a 1 km scale and increased linearly with grassland cover (improved and rough grassland). Areas predicted to experience high probabilities of hedgehog roadkill occurrence were therefore in urban and suburban environments, i.e. where a mix of urban and grassland habitats occur. These areas covered 9% of the total area within the national British road network. Used alongside evidence on the persistence with which hedgehog roadkill are recorded in a given location over time, the HSM framework can help to identify priority areas for mitigation measures.