We have released Britain’s rarest lizard back into the wild

Our conservation team released the final 80 juvenile sand lizards, one the UK’s rarest reptiles, onto Eelmoor Marsh Site of Special Scientific Interest, near Farnborough, in the last phase of a three-year release plan and research project

Once common across heathlands of southern England, sand lizard numbers have decreased dramatically due to habitat loss and fragmentation. They are now only found in a handful of heathland and dune sites in southern England, Wales and Merseyside. 

The focus of the intensive three-year research, led by Rachel Gardner, PhD student at Marwell and University of Southampton, has been monitoring the animals following their release.  

Rachel’s research has included evaluating the behaviour, habitat use and survivorship of individuals (hatchlings and yearlings), which are uniquely identifiable by their individual spot pattern.  The study has been able to directly observe differences in activity across age groups as well as gain insights into their establishment on site. 

In 2018, as a first for the species following reintroduction, tiny radio tags weighing less than 0.3 grams were used to assess the animals’ activity within a complex microhabitat and build a clearer picture to help conserve this cryptic species. 

Rachel says; “We have seen some unexpected behaviours, for example, some individuals travelled over a hundred metres away from the release site within just a couple of weeks. Considering the size of the animals [a few centimetres long] and the complexity of the heathland environment, this is quite a distance in such a short space of time.”

Rachel continues: “It’s been a privilege to work on this project and observe the sand lizards in such detail. Not only is Marwell Wildlife contributing to the wider reintroduction programme by breeding them in captivity for release into their natural environment, but we hope the research will help inform and make recommendations for the reintroduction protocol in the future, and therefore help optimise its conservation success.” 

Marwell is dedicated to restoring habitats and conserving locally extinct species. As part of its delivery, we are home to a captive breeding population of sand lizards in a custom-built vivarium, off show to the public. Each year, eggs are carefully excavated and artificially incubated to optimise hatching success. Hatching occurs after six to seven weeks and biometrics of the juvenile lizards are then taken before transferring them to smaller outdoor vivariums until release.

This year’s release brings the total count of sand lizards reintroduced to Eelmoor Marsh to over 240 individuals, with the aim to establish a self-sustaining population, at a site which would have fallen within the species’ indigenous range. 

Eelmoor Marsh, owned by QinetiQ and managed by Marwell Wildlife, has been restored to “favourable” condition following more than 20 years of targeted habitat management. An area closed to the public, it has allowed Rachel to monitor the finer details of the sand lizards’ ecology with no unnatural disturbances.

Alongside key partners, including the Amphibian and Reptile Conservation Trust and with support from Natural England, we have contributed over 2,000 sand lizards for release in Southern England and hope to continue conserving this specialist heathland species.