Wildlife Monitoring

Grass snake found during reptile monitoringCity of London ecologist shows a Grass snake to volunteers.

Snakes on Hampstead Heath

Hampstead Heath has a population of grass snakes (Natrix helvetica). This non-venomous species is the UK's largest terrestrial reptile, and are found around freshwater habitats where they hunt amphibians. Hampstead Heath’s network of lakes and ponds make it a favourable area for the grass snakes, which likely form the closest significant population to Central London.

Grass snake numbers have declined in recent years in the UK, partly due to the loss of suitable egg-laying sites and decreasing wetland habitats. They are now a protected species and Heath Hands are aiming to help them. Working with ecologists, we have created refuges to encourage population growth, including making habitats near the ponds wetter and more open to offer hunting and basking areas, creating potential egg-laying sites and constructing hibernacula where the snakes can overwinter.

We monitor the grass snake population on Hampstead Heath to assess their distribution and establish whether our work is having a positive impact on their numbers. Our volunteer Wildlife Monitors have been surveying the population since 2006 by setting up basking places for the snakes and checking them regularly for signs of activity. Volunteers have already gathered hundreds of grass snake records. These have allowed us to build up a database of key areas for the snakes as well as to guide habitat management works and ways in which these reptiles may be protected in the future.

To get involved in this project click here.