One day as I was walking past Bourne Pond in Colchester, I was shocked to see a Red-eared Terrapin (Trachemys scripta elegans) sunbathing on a log. I was able to get quite close to it to get the following photo:
I know that terrapins are an alien species to the UK and so I was unsure on what action to take. I told the RSPCA about it, but they can only collect them if they are sick or have an injury. It looked fine, so I just reported it to the Alien Encounters site instead, which is dedicated to non-native/alien species within the UK. Since my first sighting, I have seen it quite a few times swimming around and sunbathing. I even saw 2 together one day, so now I’m not even sure how many there are in this pond.
I was initially concerned about the native wildlife in the pond because the Terrapins have been known to predate on fish and waterfowl nestlings. The pond however, contains lots of fish; I have seen the nestlings grow up and I often see Kingfishers, Herons and Shags using the pond. This is a good sign and so I’m hoping their impact on the native pond life is limited.
How did Terrapins get in our ponds?
Astonishingly, Red-eared Terrapins were originally native to Britain around 8000 years ago. They then returned in the 1980s when there was a ‘Teenage Mutant Ninja Turtle‘ craze, which lead to the importation of Terrapins from the USA, into the British pet trade. When the pet Terrapins became adults, they were much larger, less appealing and harder to maintain. As a result of this, many adults were released into wild ponds and rivers. There was estimated to be at least 4000 feral Terrapins within the UK.
These Terrapins are able to survive in our British climate, however, lower temperatures prevent them from successfully breeding. Annual mortality rates of feral Turtles and Terrapins within the UK, is estimated at 40-80%.
There are many other non-native species found in the UK, including North American Bullfrogs, American Signal Crayfish, American Mink, and Japanese Knotweed.
For anyone interested, you can purchase the following book from Amazon called ‘Non-native Species and Their Role in the Environment‘.