2025 Registrant Impact | Habitat defragmentation

Connectivity between habitats

Alongside my role with National Highways, I am Co-Founder of Rebuilding Nature, an alliance of cross-sector organisations who want to invest in nature now because it is critical national infrastructure.  For all the wonderful complexity of nature, the prescription for nature recovery is simple: more, bigger, better and joined-up habitat. To deliver this Rebuilding Nature are calling for the creation of a Strategic Nature Network – a UK-wide physical nature network that protects and connects core habitat areas to allow the free movement of plant and animal species. With colleagues and collaborators, and 70 corporate members signed up within its first year, we’ve made significant progress – but more is needed.  Developed by a volunteer technical advisory group, the first concept map of the Strategic Nature Network will be launched in June. Sir John Lawton, leader of the “Making Space for Nature” review will deliver a keynote address. 

Linear infrastructure such as that managed by National Highways has a particular role to play in achieving joined-up habitat.  Our road network offers both positives and negatives for nature connectivity. We own 30,000 hectares of vegetated land in our road verges, the area of the Isle of Wight.  These verges are important habitat in themselves, but they also offer corridors for nature that pass through the landscape, allowing species to move and migrate between adjacent core habitat areas.  While connectivity is improved along our verges, heavily trafficked roads act like security fences, preventing species movement across our roads, fragmenting habitat on either side. 

Habitat defragmentation can be achieved through the construction of nature crossings; tunnels, pipes or green bridges that permit species to cross the road. Increasingly we are including these within the design of our major enhancement schemes.  In January 2025, the beam-lift took place for the Cuckrow bridge over the A3 near Wisley, constructed as part of an upgrade to the M25 junction.  This is the first heathland bridge in the UK, 30m wide it reconnects two Heathlands, both sites of special scientific interest with international designation covering 660 acres, that were severed by the construction of the A3 50 years ago. Another two bridges are being built in Gloucestershire and Cornwall, also part of major construction projects.  

While this is to be celebrated, it doesn’t match the investment that is being made in nature connectivity across the world. For example, in 2005 the Dutch put a plan in place to construct nearly 200 ‘ecoducts’, or nature crossings, of which 80 were green bridges. I am building the case for a national defragmentation programme, assessing where the most important points of nature severance are across our network, and engaging with Local Nature Recovery Strategy authors and environmental groups to encourage ambition about reconnecting habitat across the country.