Habitat Selection of Invasive Sika Deer Cervus nippon Living in a UK Lowland Heathland-Woodland-Grassland Mosaic: Implications for Habitat Conservation Management

Understanding the factors determining the choice and use of habitats by invasive species is key to the conservation management of habitats and may also enable species to be harnessed as conservation tools. Here we explore the habitat use of an invasive population of sika deer, Cervus nippon on internationally important heathland in a landscape of heathland, grassland and woodland in southern UK. We used radio telemetry to test two hypotheses 1) grasses form a major part of the diet of non-native UK sika deer throughout the year 2) deer select grassland habitats above other habitats available. Results showed that although grasses form a major part of their diet, the strongest habitat selection was for heathland, the habitat that offered the least nutrient reward but which offered a source of roughage in the diet and some harbourage from human disturbance. This has implications for the conservation management of heathlands used by sika deer as it strongly indicates that heathland is a vulnerable habitat due to being favoured by sika deer but that its vulnerability can be reduced by coupling population control with targeted habitat management action such as increased disturbance or the removal of harbourage.