ZSL lends a helping hand to save the endangered pool frog in the UK

by ZSL on

The end of the summer marked the beginning of an exciting new chapter for over a hundred young pool frogs released into the wild in Norfolk this year. The pool frog (Pelophylax lessonae) became extinct in the 1990s in the UK but thanks to collaborative efforts by Natural England, the Amphibian and Reptile Conservation Trust (ARC), Norfolk Wildlife Trust, ZSL and partners, the species persists in protected areas where ancient ponds have been restored to provide optimal habitat. 

Photo - Close-up photo of a pool frog held and scanned with a small hand-held device

The Disease Risk Analysis and Health Surveillance (DRAHS) team at ZSL were on hand throughout the spring and summer to assist with the project. Tadpoles were raised from collected spawn in a special quarantine unit established by ARC. By raising the tadpoles in strict bio-secure conditions the tadpoles were given the best possible chance of developing into healthy metamorphs free from the risk of predation and other threats in the wild. DRAHS wildlife vets Dr Tony Sainsbury and Dr Tammy Shadbolt and herpetologist Dr Christopher Michaels from ZSL’s reptile house visited the facility on several occasions to provide advice on health and husbandry. Before the grown metamorphs were reintroduced checks were carefully carried out on the young frogs to ensure they were in a good state of health at the point of release into the wild. 

Photo - DRAHS wildlife vets Dr Tony Sainsbury and Dr Tammy Shadbolt carrying out health examinations on pool frogs out in the field
DRAHS wildlife vets Dr Tony Sainsbury and Dr Tammy Shadbolt carry out health examinations on pool frogs from the reintroduced population.

The DRAHS team were also busy out in the field during the season examining the health of the wild adult pool frogs already present at the release site. Detailed examinations involved a thorough check of each frog’s body and limbs, listening to the heart and lungs using a stethoscope and gently palpating the coelom as well as taking important measurements such as bodyweight. Dr Tammy Shadbolt explains “It’s important to ensure that the health of the reintroduced free-living  pool frog population is closely monitored and maintained. We are hopeful that next year a surge in numbers might be seen as a result of this carefully implemented project thus helping to safeguard the future of the species in the UK.”  

Visit ARC's website to find out more about pool frog conservation.

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