eDNA for water frogs around Lynford Lakes, Norfolk

In 2025, putative marsh frogs have been sighted in water bodies near Ickburgh, Norfolk. This species poses a significant threat to the Critically Endangered native northern pool frog through disease transmission, competition, and hybridisation. Ickburgh is some 12km from the known native pool frog population at Thompson Common. The northern pool frog became extinct in the UK by the 1990s but has been successfully reintroduced through a collaborative project led by Amphibian and Reptile Conservation and Natural England. Reintroductions began in Norfolk in 2005, with a second release at Thompson Common from 2015-2021. Protecting these populations is critical to securing the future of this rare amphibian. A national contingency plan is in place to respond to an incursion of invasive non-native animal in England. Natural England is the lead agency responsible for the management response. The proposed activity will use eDNA sampling to determine the extent of marsh frog presence/absence across selected water bodies, starting near native pool frog habitats and moving east to west to minimise disease risk. Outputs will include a spatial distribution map to inform Natural England and partners on management control options. The project requires the supply of eDNA water sampling kits for freshwater ponds/lakes, and use of a metabarcoding to detect the presence or absence of Pelophylax species using an amphibian assay (include other amphibians in the data as well).