Blean Bison Tunnels

Client Organisation

Kent Wildlife Trust have constructed two out of four bison bridges for the UK's first wild bison herd within Blean woodland.

Type of Work

Protect Species Surveys, PEA, EcIA and ECoW.

Background

The bridges will allow the bison herd to access 200 hectares of West Blean and Thornden Woods in Canterbury.

The bison have been placed in the woodland to boost biodiversity and shape the habitat around them to make it more climate resilient. 

They are often called ‘ecosystem engineers’ they strip bark from trees, creating standing deadwood which supports insects, birds and bats and they dustbathe, creating sites that attract burrowing insects. Their sheer size means they push through and trample dense vegetation, creating light and space for wildlife to thrive. 

Project Overview

Adonis Blue Environmental delivered a comprehensive ecological service for this woodland project, supporting it from initial assessment through to construction and ongoing monitoring.

Early Assessment & Surveys

The project began with a Preliminary Ecological Appraisal (PEA) to establish baseline ecological conditions and identify potential constraints. This was followed by a suite of targeted protected species surveys, including bats, reptiles, dormice, birds and the heath fritillary butterfly.

Reptile surveys were undertaken at an early stage, prior to the construction of the bison bridges, to inform mitigation strategies and ensure compliance from the outset. Ground-level tree assessments were also carried out to identify potential bat roost features, alongside detailed dormouse surveys, butterfly surveys and bird surveys to understand habitat use across the site.

Licensing & Impact Assessment

Survey findings informed protected species licence applications and the preparation of a detailed Ecological Impact Assessment (EcIA), ensuring that all potential impacts were fully assessed and mitigated in line with best practice and legislation.

Construction Phase Support

During construction of the bison bridges, Adonis Blue Environmental provided Ecological Clerk of Works (ECoW) services. This included supervising groundworks such as scraping activities to ensure sensitive ecological features were protected. All works were carefully monitored to ensure full compliance with ecological legislation and agreed mitigation measures.

Special attention was given to the handling of ancient woodland soils. Soil layers were carefully separated during excavation (topsoil and subsoil) and reinstated in the correct order, preserving the integrity and function of this valuable habitat.

Ongoing Monitoring

Following completion of construction works in October 2024, Adonis Blue Environmental continues to support the project through ongoing ecological monitoring. This includes reptiles, bats, and dormice, in line with the EcIA and licensing requirements, ensuring that mitigation measures remain effective and the site continues to support its protected species.

Outcome

This project demonstrates Adonis Blue Environmental’s ability to deliver end-to-end ecological consultancy services—balancing development needs with the protection and enhancement of sensitive woodland habitats.