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Preliminary Ecological Appraisals (PEAs)

A Preliminary Ecological Appraisal (or Phase 1 Habitat Survey as they are sometimes known) is the first stage in assessing the biodiversity and protected species of a proposed development site. Essentially, they aim to rapidly assess the ecological value of the land and the impact a project will have on it. They are often required as part of the planning application process so that mitigation measures can be put in place.

There are two main elements to a PEA:

Ecological Desk Study

A desk study collates information about the site and the surrounding area to provide background information. This will use the local biological records centre and other resources to find records of protected species in the area. It will also identify whether there are any designated sites within a set distance of the project.

Site Walkover

In addition, a site visit will take place. During a walkover, the ecologist will classify and map the habitats on site. They will also look for the presence of, or potential for, protected species, both within the site boundary and in adjacent areas.

The PEA Report

Following these, the ecologist will compile a report that combines all the information gathered. This will identify if any more detailed surveys need to be carried out due to signs of, or potential for, protected species, such as bats or great crested newts.The report will also set out what mitigation measures will be required in line with environmental legislation. In addition, it will identify opportunities for ecological enhancement. The Environment Act 2021 includes a requirement for most development projects to increase the site’s Biodiversity Net Gain by a minimum of 10%, and this has consequently become an increasingly important aspect of the planning application process.