Written by Ellia Cobb, Transforming Lives Trainee
Disease is a huge issue for our amphibian population, Ranavirus and Chytridiomycosis being two of the main diseases that threaten our native species. It is thought that these diseases were introduced by non-native species being released into the wild. One third of all amphibians are at risk of extinction with heavy declines across the globe.
Ranavirus is somewhat new to the UK and is mainly found in common frogs, some of the symptoms are skin ulcers which are commonly seen on the skin around the legs and pelvic area. The frogs infected will also suffer from internal bleeding which you may only be able to identify from redness around the mouth and cloaca. Frogs may also show signs of lethargy, but they won’t always show obvious symptoms of this virus. Ranavirus is only active during warmer temperatures, but can be devastating to pond populations around summer time, it is fatal and can affect the entire pond population.
Chytrid infection has been responsible for mass mortalities within the UK’s amphibian population and in some cases, it has caused extinctions. Most native natterjack toad populations have tested positive for the infection, but seem to be unaffected. That however, doesn’t stop them from spreading it to other amphibian populations. Evidence suggests that chytrid causes death by preventing sufficient uptake of salts through the skin. Amphibians need these salts for their circulation and without this, their hearts cease to function. Symptoms of this include ulcers, reddening, shedding and unusual behaviours.
There are steps everyone can take to prevent the spread of amphibian disease:
- Do not transfer animals or plants from one pond to another.
- Do not purchase wild-caught spawn, tadpoles or adult amphibians online. Not only is this against the law, but you do not know the origin of the animals.
- Do not release pet/exotic amphibians into the wild. It is against the law and can cause severe damage to not only the released amphibian, but the local population too.
- If you suspect disease in an amphibian, report it to Garden Wildlife Health