New Amphibian Arrivals

Tuesday, July 6, 2021

As we all know new residents are moving into Berewood all the time; but this June some rather unexpected new arrivals have been recorded in the SUDS ponds on site. First alerted by landscape contractors working along the River Wallington to strange loud calls coming from the vegetation around one of the SUDS ponds, it didn’t take long before the identity of the creatures was resolved – a group of marsh frogs!

These frogs can be up to 17cm in size and their distinctive call can travel hundreds of metres. They are also known as the laughing frog because of the noise they make when calling to one another:

Marsh frogs were introduced to Romney Marsh in Kent in the 1930’s. They are now widespread in Kent and Sussex and can be found at various locations throughout southern England. Things get complicated however, as marsh frogs and two-closely related species the edible frog and the pool frog are capable of inter-breeding and all are present in England. Therefore the exact identity of the frogs at Berewood is yet to be confirmed, but they are considered most likely to be marsh frogs.

The question is, how did they arrive in Berewood? There are no known populations in this part of Hampshire and they have never been recorded during surveys of ponds around the site previously. Given how noisy they are it is unlikely they have been overlooked. Could they have been introduced to the SUDS, accidentally on plant material or deliberately through human intervention? We shall probably never know but releases of non-native species, such as the marsh frog, into the environment can cause problems for native wildlife. Introduced amphibians can prey on native species and act as disease carriers, potentially putting at risk populations of our native amphibians.