Keeping habitats connected: Does wildlife mitigation work?

Loss of biodiversity due to anthropogenic impacts is one of the major global challenges of our time. Roads can act as barriers, or cause mortality, and in areas where traffic speed/road density are high, roads exert strong negative local impacts on wildlife populations (Forman and Alexander, 1998). Across Europe, major increases in road infrastructure and usage have been recorded (European Commission, 2014), and are continuing. Associated wildlife vehicle collisions (WVCs) are increasing, and for some species (e.g. otters) WVCs are the main cause of mortality (Jancke and Giere 2011). Mitigation offers viable solutions to reducing WVC's, and retaining biodiversity, but its efficacy is rarely assessed. Here, we will address this knowledge gap.

The overall challenge is to determine how modifications to road management via mitigation alter animal behaviour, and potentially aid conservation. This work will build an important case study of the association between anthropogenic activities and road mortality of wildlife, including key flagship conservation species, such as otters.

This PhD proposal seeks to assess the behaviour of wildlife in response to roads, habitat and road mitigation solutions. As such, the proposed work offers an exciting opportunity to carry out field-based research with spatial modelling, in an applied area of wildlife conservation with international management implications. The work will be carried out in collaboration with Animex International, a company specialising in wildlife mitigation solutions (see https://animexfencing.com/). Analyses will be based on an extensive and unrivalled dataset of ca. 70,000 records of wildlife vehicle collisions, provided by citizen science projects at Cardiff University (www.projectsplatter.co.uk and www.otterproject.cf.ac.uk). Associated data will be collated quantifying a wide range of natural and anthropogenic influences, including road lighting, noise, and highway design (e.g. barriers, crossings), traffic volume and speed, landscape features (e.g. road/river intersections), and habitat. These data will be collated using Geographic Information Systems (GIS), from satellite imagery using existing digitised environmental data. The student will explore the species-specific associations between habitat, anthropogenic influences and wildlife vehicle collision rates. In addition to analyses using existing datasets, field experiments to test the impact of wildlife mitigation solutions on animal behaviour will be carried out at Animex International's field sites in the UK and North America.

Both our statistically developed risk models and empirical outputs will be used to develop predictive models of risk for dissemination to stakeholders (Wildlife Trusts, Trunk Roads Agencies), in order to assist the development of targeted mitigation to aid conservation management.