A recent study warns that invasive two-metre-long snakes are breeding inside walls and attics across the UK, according to scientists. The Aesculapian snakes, which can grow up to 7ft long, are not native to the UK. These snakes were locally extinct during the last Ice Age and were not seen widely in the UK for 300,000 years. However, they have now become an invasive species, with researchers reporting their presence in warm corners of the country.
The Aesculapian snakes were introduced to Colwyn Bay in North Wales in the 1970s after an escape from the Welsh Mountain Zoo. Previous sightings have placed these snakes near the London Zoo area in Regent’s Park and close to Bridgend in South Wales. These non-venomous snakes primarily feed on rats.
Researchers are puzzled by how these cold-blooded creatures survive in colder environments and are exploring how invasive species like the Aesculapian snakes are adapting to climate change, habitat changes, and human transport activities.
To better understand the distribution of these snakes in the UK, researchers radio-tracked and studied around 13 male and eight female snakes daily over two active seasons between 2021 and 2022. The study found that the snakes make use of “human features” such as attics and wall cavities in houses. Male snakes show a preference for buildings while females prefer woodland areas, according to scientists.
The researchers also discovered snake eggs inside a compost heap at a house, indicating that the snakes are actively breeding in these areas. These observations of Aesculapian snakes actively seeking shelter in inhabited buildings, climbing large structures to access attics, and using wall cavities are considered unusual behaviours compared to native UK snake species.
During the study, five out of the 21 Aesculapian snakes tracked were reported to have died, with three killed by cars and one becoming a victim of cannibalism by another male snake. This behaviour suggests that the snakes may be using hedgerows and culverts to expand into new areas while avoiding roads.
Overall, the study sheds light on the invasive behaviours of Aesculapian snakes in the UK, raising concerns about their impact on ecosystems and habitats. Further research is needed to understand how best to manage and mitigate the presence of these snakes in urban and rural environments.