Over the past few years RAVON have been developing their conservation programme for the native grass snake (Natrix helvetica). This programme has included specific habitat management for grass snakes, to enhance their breeding success and thereby increase the sustainability of populations. One of the most successful interventions has been the creation of egg-laying heaps, which have proven to be a simple, yet effective way of boosting juvenile recruitment. The key to the success of these is the composition and structure of the egg-laying heap, such that it maintains an even temperature, perfect for incubating grass snake eggs, but is not too compact, so that the animals can move around within it.
Take a look at their advice leaflet here. for further information.