Reptile surveys at Blewbury Nature Reserve

This year’s reptile survey season (March to October 2025) is well under way and as things warm up, so too do our team of volunteers who have upped their efforts to one survey per week! This will provide us with an excellent data set across the season. Our surveys consist of carefully looking under 15 strategically placed “Refugia” (mats) and a quiet walk-over transect that takes in the various habitat types found across the reserve. Since 30 April, our team has found at least one Grass Snake (Natrix helvetica) every week including both males and females and, encouragingly, a juvenile that would have hatched late last summer. Grass Snakes breed around April / May and are our only egg-laying snakes in the UK. The female lays a clutch of 10-40 eggs around June to July with the young hatching as a perfect miniature adult around August to September. It is wonderful to know that this beautiful snake is breeding at our reserve.

Similarly, we have consistently recorded the Common Viviparous lizard (Zootoca vivipara - formerly Lacerta vivipara. Common lizards also mate in April to May but unlike the Grass Snake, the female produces three to eleven young in July having incubated her eggs internally and ‘giving birth’ to live young, which is the meaning of the name Viviparous. We have also found a grass snake’s skin. This shedding process is known as “sloughing”, pronounced “sluffing”, and enables the snake to grow, help maintain healthy skin, heal injuries and remove parasites. Male grass snakes typically shed their skin twice a year and females once, just before laying eggs.

We will be sending our slough specimens to ARC (Amphibian and Reptile Conservation) who work with ARG UK (Amphibians and Reptile Groups of the UK) to collect samples across the UK. They extract DNA from these sloughs to build up a 'Reptile Genebank' that can be used for long-term studies into the effects of population isolation through habitat loss or development (a potentially important factor in the decline of all UK reptiles). The condition of the sloughs is also used to tell them more about the impact of other external factors such as trauma from predator attacks, or parasites that may be affecting them. We have yet to see our legless-lizard friend, the Slow Worm or an Adder but we live in hope! Many thanks to all the volunteers for their enthusiasm and help.

James Morgan