Reptile Survey

A range of habitats may support reptiles, including rank grassland, heathland, scrub, sand dunes, brownfield sites, gardens, and wetlands. Where these habitats are deemed likely to be affected by project proposals, a reptile survey may be required, which aims to establish presence/ likely absence, and distribution of reptiles on site.

Reptiles are typically found in a broad range of habitats throughout Britain, though certain species have very restricted geographic ranges. Six species of reptile are found in Britain. Though several are still relatively common, their populations have declined over the last century, primarily due to habitat loss and degradation. They are protected under UK law, making it an offence of kill, capture, or disturb them, though their habitat is not specifically protected. Smooth snake and sand lizard are afforded additional protection, and works affecting these species are subject to licensing procedures. 

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The appraisal is used to inform the emerging scheme design, enabling significant ecological effects within the zone of influence to be avoided, mitigated, or compensated for, where necessary. This ensures the continued favourable conservation status of reptiles, post development, and ultimately compliance with nature conservation legislation and planning policy. 

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Presence/ likely absence surveys comprise the periodic direct searching of naturally occurring and deployed artificial refugia in suitable habitat across the site. The inspections are based on an index of probability scoring system, where different months within the survey season entail varying likelihoods of reptiles being detected, consequently eliciting different survey effort scores for each each species, each month. Once installed, the refugia are left undisturbed for at least two weeks, prior to commencement of the survey inspections, thereby allowing reptiles sufficient time to colonise and subsequently utilise the features. The refugia are then systematically inspected on multiple occasions, non-consecutively over the course of the survey season, until the minimum standard effort units are achieved. If the presence of reptiles is established, the population size class will be determined by comparing two metrics: peak count; and habitat suitability assessment, with the higher of the two values being adopted. Additional visits as part of a translocation exercise may be required, if adequate avoidance or on-site mitigation and compensation is not deemed possible. The site survey is typically supplemented by a desk study, utilising maps and aerial photographs of the surrounding area to identify ecological connectivity, and published records of reptiles, purchased from the local records centre.

Requirements for any necessary avoidance, mitigation, or compensation measures will be identified, and opportunities for ecological enhancement will be outlined, to integrate on-site biodiversity net gain into the scheme at an early stage, where possible.​ If the proposals are deemed likely to adversely affect reptiles, a mitigation strategy may be required, prior to the commencement of works.

Reptiles surveys are seasonally constrained and protracted, making it prudent to plan ahead and consider ecological issues early on in the planning process. A robust reptile survey at an early stage in project planning and design can therefore deliver significant benefits, avoiding potentially costly and time-consuming delays.​

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When

Presence/ likely absence surveys must be undertaken between March-mid October inclusive, though ideally predominantly during the optimal months of April, May, June, or September.