Hampstead Heath's ecology team say that new measures, including creating small ponds to increase the number of amphibians and vegetation piles for egg laying, will have a positive effect on the grass snake's population.
Grass snakes are the only recently recorded species of native reptile present on the heath.
Conservationist Adrian Brooker said:
"To have a breeding population - even a small one - so close to the centre of London is very special and gives an indication of the 'health' of the heath's ecosystem because it tells us about the well-being of the snake's main prey, such as frogs and newts.
"Because of a decline in suitable habitat, grass snakes are now listed as a priority species in the United Kingdom Biodiversity Action Plan, so we are very keen to increase their numbers."
In reality Brooker says it is unlikely that many other types of reptiles other than grass snakes will flock to the Heath. Adders and common lizards have been extinct for nearly a century and would have to fight off pressure from people as well as cope with the transformation from open heathland to woodland during this time. However, it is hoped that recent work by Hampstead Heath's conservation teams to restore lost heathland may go some way towards reversing this trend.
The only other reptile which may also be present on Hampstead Heath is the slow worm, but they stay very well hidden and were not found in this current survey. Records show they were still present in the 1990s.
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