Trackadder - Reptiles continue to thrive following major project relocation

Adders, viviparous lizards, slow worms and grass snakes continue to thrive in Gloucestershire thanks to the work of the A417 Missing Link team.

In total, the project team has safely relocated over 2,000 reptiles while construction is under way.

Since then, the team have been collecting data on all of the reptiles and further research in particular on adders, making note on their sex, scale patterns, weight, and breeding condition to go alongside the telemetry research previously conducted.

In 2023, 10 adders were fitted with a radio tag post-hibernation to enable the monitoring of their movements at receptor sites.

The adders were tracked over a period of approximately 65 days, until the tags were naturally shed. This tracking effort not only provided valuable insight into individual movement patterns during the breeding season but also led to the discovery of previously unrecorded reptiles.

Initially, released adult adders remained close to the release site, but post-breeding, many dispersed between 100 and 300 meters. Some females, however, continued to stay near the release area. Encouragingly, newborn adders have been found at all sites later in 2023 and into 2024.

Some adders have dispersed beyond the initial release areas, suggesting the need for broader landscape-scale surveys to identify newly occupied habitats. Over the next five to 10 years, a clearer and more accurate picture of population survivorship and site expansion is expected to emerge.

The goal is to establish robust, well-distributed populations with a varied age structure across all species.

This work highlights the importance of ensuring that any future reptile translocations are supported by well-managed, connected landscapes and strong, collaborative relationships with landowners. Natasha James, Senior Ecologist for Kier, said: “We’ve undertaken an enormous amount of ecological and environmental work throughout construction, and local specialists have been hugely helpful in achieving this.

“We’ve been particularly diligent with the reptile translocation on the A417 Missing Link scheme – and it’s really pleasing to see that the reptiles have settled into their homes and continue to thrive.

“The work will maintain populations of protected species in the area and help to enhance biodiversity once the construction work is completed. The data we collect will continue to give us an insight into reptiles and their behaviours and hopefully go on to inform best practice guidance for future schemes.”

Celine Acard, Senior Project Manager for the A417 scheme, said: “We’re really proud of the work we’ve undertaken to protect the ecology and environment in the area, and the reptile relocation and data collection work is a glowing example of this.  

“The design of the road has been carried out in the most sympathetic way for local people, the travelling public, wildlife and the environment.  

“As a landscape-led scheme, we have worked hard to enhance habitats in keeping with the sensitive Cotswolds environment and look forward to sharing more of our work as construction progresses.”  The landscape-led A417 scheme is not only creating a vital transport link in the Cotswolds, but also incorporates world-class environmental practices that respect and enhance the surrounding landscape and habitats, including:

• Dual Use Crossings: Two more partially planted crossings will be erected to allow traffic to flow over the main road.

• Biodiversity: The planting of over 100,000 trees and over 80 hectares of calcareous grasslands to ensure the scheme leaves a positive biodiversity legacy.

• Material Recycling: Excavated site rock is recycled on-site using six crusher plants, breaking down the rock to be used as the new base layer for the road.

• Bat Underpass and Structures: Dedicated bat underpass, bat boxes, structures and habitats such as dead hedging, to support local bat populations and reduce disruption to wildlife.

• Bird Fencing: During construction, high fencing will alter the flight paths of birds to limit collisions with cars.

• Animal Translocation: Translocated over 2,000 reptiles and over 100 Roman snails to ensure the scheme had minimal impact on nature in the area.

• Landscape and Acoustic Bunding: Extensive bunding designed to reduce noise impact and enhance the visual appeal of the landscape.

• Drystone Walling: 7.5km of drystone walling, in keeping with the current landscape and supporting biodiversity.

• Repurposed: A repurposed section of the existing A417, transformed into a ‘purpose-built’ restricted byway for WCH users, including disabled users and carriages, planted with species-rich grassland, native hedgerows, and trees.