Abstract
The demand for housing and industrial, recreational and commercial development is placing increasing pressures on protected species and their habitats in the UK. When a development threatens an area containing a species that is afforded legal protection, suc as the great crested newt, there is a legal obligation to undertake appropriate mitigation measures to reduce the impact of the development on the species. Under current guidelines, a typical mitigation involves pre- and post-development population and habitat assessments, habitat management and enhancement and actions that will reduce the likelihood of animals being killed by the development activity (e.g. translocation or exclusion of the population from the development site). However, on a national scale, there is a paucity of information concerning how great crested newts are faring at sites subjected to mitigation actions. This project aims to provide an assessment of the effectiveness of development mitigation measures for great crested newts since revised guidance on best practice was published in 2001. Twelve sites will be selected for assessment from existing licensing information held by Defra and Natural England. Information on the pre-development population status and habitats at each of these sites will be collated from licence returns and any other surveys carried out at the time. The number of ponds, habitat types, and levels of fragmentation will then be assessed for the area within 1 km of the development site using GIS and Google Earth. Each site will then be surveyed for great crested newts using standardised survey protocols to determine (1) presence-absence; (2) population density; and (3) peak counts. In addition, Habitat Suitability Indices will be calculated for each site and levels of isolation and fragmentation determined. The population assessments from each pond will be compared to those from a wider sample of control (i.e. unmitigated) ponds for which there are existing data. The population assessments will also be compared to those obtained from a sample of sites subjected to mitigation prior to the 2001 guidelines: this will allow an assessment of the impact of the improved guidance. On a wider scale, modelling and mapping will be used to explore the likely affects of mitigation actions on favourable conservation status of great crested newts. Different types of mitigation actions will be evaluated in relation to current population and habitat status, and recommendations provided to refine mitigation protocols and standardised population assessments. The results of the project will allow the relevant government agencies to perform their statutory duties more efficiently and more cost-effectively. Equally, scientists, landowners, developers and professional ecological consultants will benefit from improved guidance for dealing with situations where great crested newts and their habitats come into conflict with development.
United Kingdom