Adder Connections aims to link two isolated populations of adders to secure the species’ survival in one of their last remaining strongholds in West Berkshire. The project has received a £113,000 grant from Natural England’s Species Recovery Programme Capital Grant Scheme and will form a best-practice case study.

Greenham and Crookham Commons in Berkshire, managed by Berkshire, Buckinghamshire & Oxfordshire Wildlife Trust (BBOWT) on behalf of West Berkshire Council, are home to two distinct populations of adders. The land management team discovered that the groups were not mixing after attaching radio tags to some of the adders to track their movements. Results showed that the snakes were unable to cross Old Thornford Road which divides the commons, and so two tunnels were created underneath the road to encourage movement.

With adders listed as a Vulnerable (VU) species, recent scientific studies suggest that only a few of the larger populations could be left in England in 10 years’ time. As small groups are at greater risk, the Adder Connections project aims to form a larger local population with a wider mix of genetics to make them more resistant to potential threats such as disease.

BBOWT’s Tom Hayward, Senior Land Manager for Berkshire, said:
“The adders are at some points only a matter of metres apart, but they may as well be five hundred miles away. We’re seeing adders disappearing from central England at alarming rates, but we know the importance of genetics to their survival and we’re hoping these tunnels will make our populations sustainable into the future. I’m looking forward to the first moment of seeing an adder using the tunnel on camera so that we know they stand a chance.”

The snake tunnels are the first of their kind in the UK but come in the wake of successful use elsewhere in Europe and America. They have been designed in accordance with expert advice, using pebbles at the bottom to aid movement, with metal fencing to guide the snakes and other small creatures through the tunnels and away from the dangers of the road.

Radio tracking and camera traps will be employed in the future to monitor the tunnel usage and if the populations are mixing. The results will have significant implications for similar projects across the country, particularly where species fragmentation is an issue.

BBOWT’s Debbie Lewis, Head of Ecology, said:
“Adders are amazing creatures. They are the UK’s only venomous snakes and can live up to 30 years, but because they are naturally cautious of humans they are rarely spotted. We know that loss and fragmentation of their habitats – and even climate change – is having a huge impact on adder numbers, and it's sad to say that this incredible creature could be extinct from our counties in the next few decades if something isn't done to help them. Most have already disappeared from Buckinghamshire and Oxfordshire, with this area of Berkshire being a vital stronghold for them.

“New and innovative thinking is needed to combat the current crisis. We hope to contribute to the wider understanding of how we can better encourage mixing among adder communities, and a successful outcome of this project could lead to it being replicated across other sites, other wildlife trusts and for this scheme to be used as a showcase for landowners. Whatever the result, we will have gained vital insight into the behaviour of these fascinating reptiles.”

A major threat to adders is human interference, both through deliberate persecution and disturbance of their nesting sites. The Trust asks that visitors do not seek out adders on the reserve, and if seen, to enjoy them from a distance as this is safer for the visitors, adders and pets. BBOWT’s seasonal wardens are present on the reserve every spring and summer to advise visitors on how to use the common safely without disturbing the precious wildlife living there.