Ecological Support for Redevelopment at Former RAF Yatesbury

Overview: 

An initial Preliminary Ecological Appraisal (PEA) and Preliminary Roost Assessment (PRA) identified habitats suitable for protected species, including reptiles, badger, roosting bats, and nesting barn owl. As a result, targeted Phase 2 surveys were carried out over the summer, with efforts coordinated to minimise site visits and reduce the carbon footprint. These surveys informed the planning process and helped guide the ecological mitigation strategy, including reptile translocation and a European Protected Species Licence (EPSL) application for works affecting bat roosts.

Challenge

In parallel, the evolving landscape design, influenced by changing drainage and archaeological constraints, required repeated updates to the Biodiversity Net Gain (BNG) assessment to reflect each iteration of the plans.

Further challenges included the confirmed presence of day and night bat roosts for common pipistrelle, soprano pipistrelle, and brown long-eared bats. A European Protected Species Licence (EPSL) will be required post-planning to permit works affecting these roosts. In addition, the site supports foraging and commuting bats along existing treelines and scrub, necessitating a sensitive lighting strategy to avoid disrupting established bat flight paths. Ahead of the construction phase, a comprehensive Construction Environmental Management Plan (CEMP) will be essential, and ecological input into the Landscape and Environmental Management Plan (LEMP) was also provided to support long-term biodiversity on site.

Approach

Reptile Surveys:
Given the extent and suitability of habitats across the 13-hectare site, hundreds of reptile mats (1m² roofing felt squares) were deployed in areas most likely to support reptile populations. Once settled, the mats were checked regularly under suitable weather conditions. The method allowed ecologists to gather population data efficiently while minimising site disturbance.

Bat Surveys:
Nine dusk emergence surveys were carried out across multiple buildings, each requiring around five surveyors. COVID restrictions prevented dawn surveys, but dusk data—collected through direct observation and bat detectors—provided high-quality insights. Acoustic analysis identified species such as common pipistrelle, soprano pipistrelle, and brown long-eared bats. The surveys also identified key commuting and foraging routes, informing a mitigation strategy and future EPSL application.

Badger Surveys:
An active badger sett identified during the PEA was monitored using night-vision trail cameras and sticky sticks. This confirmed the sett’s use and allowed ecologists to map badger movement across the site. Several inactive setts were confirmed as disused, enabling the design to avoid the active sett and eliminate the need for a licence.
Findings from the desk study, PEA, and Phase 2 surveys were used to prepare an Ecological Impact Assessment (EcIA). A Biodiversity Net Gain (BNG) Assessment, using DEFRA Metric 3.0, was updated iteratively to reflect evolving site designs and to support planning submissions.