Sand Lizards are one of the UK’s rarest and most elusive reptiles. They are restricted to sandy heathland and sand dune habitats in the south and west of the UK which provide the warm microclimates that they need. They also bury their eggs in hot sand to incubate until they are ready to hatch, so open, sunny, and undisturbed sandy areas are essential. Even in these warmer habitats, Sand Lizards will typically hibernate for longer than other reptiles to avoid cooler conditions, sometimes even from the end of August.
Given Sand Lizards are so reliant on warm, sunny microclimates, it’s hard to imagine that they could ever survive or breed on a Scottish island. Yet, there is a single population of Sand Lizards which has been thriving on the Isle of Coll off the west coast of Scotland for 50 years. In the 1970s, scientists released a population of Sand Lizards on Coll in an experiment to see how they would cope so far north, and they have fared surprisingly well. Coll has plenty of open sandy dunes which are largely undisturbed given the low number of visitors to the island, with patches of vegetation to hide in should a predator appear. Furthermore, Coll is known for being extremely sunny, and as a result, the island may be far better suited to Sand Lizards than we would first think.
Sand Lizards seem to be very dependent on habitats which are being degraded and lost due to factors such as increased urbanisation, human disturbance, dune erosion, and heathland fires. However, if their UK range were extended, perhaps there is still some hope for this rare lizard. Sand Lizards are often thought to be limited by latitude, yet they appear to be thriving on Coll and other more northerly ranges outside of the UK such as Sweden. So why are they so rare here? Well, in addition to limited habitat, it is very difficult for Sand Lizards to colonise new areas due to a lack of habitat corridors and unsympathetic land management. Reptiles generally tend to be an overlooked group, and land management rarely takes their needs into consideration.
The Sand Lizards of Coll demonstrate that they do have the potential to occupy a wider range in the UK than we might think, but achieving this would require more wildlife corridors, and more reptile-friendly approaches to habitat management. This would enable increased movement and give Sand Lizards more opportunities to colonise new habitats, and perhaps provide some hope for this dwindling species.