Gardeners and wildlife lovers are being urged to be ‘frog friendly’ and leave frogspawn alone. Please do not be tempted to move it as you could be spreading potentially fatal diseases to frogs and other wildlife.
A female frog may lay thousands of eggs each year but only a tiny percentage will survive into adulthood. This is because spawn, tadpoles and froglets have numerous natural predators, including some of our favourite garden birds, and they are also very susceptible to disease and pollution.
In the late 1980s, unusual mortalities of common frogs were reported in the south east of England. Frogs were found to be suffering from a variety of symptoms, sometimes with secondary bacterial infections. The culprit was identified as Ranavirus*, possibly spread from North America through the commercial importation of bullfrogs or goldfish.
Trust Senior Conservation Officer Neil Pilcher says, “If you think there’s a huge amount of frogspawn in your pond you may be tempted to move some to another pond or stream, particularly local ones that already have spawn. But this can be extremely damaging to frogs, toads and other wildlife too. Diseases such as Ranavirus are a very real concern, but also is the fact that the contents of your bucket could accidentally transfer invasive non-native plant species to new locations where they could do significant damage to the natural environment.
“It’s a tough life being a frog, but nature knows best. Please help by doing absolutely nothing!”
*Ranavirus causes two forms of disease in frogs: skin ulcers and internal bleeding. In the first case ulcers can readily be seen on the skin, especially on the underside of the pelvic region and on the hind limbs and feet. Bleeding is sometimes evident from the mouth or cloaca or as a reddening of the underside. This reddening led to the name ‘red-leg’ disease, yet this is a misleading term for Ranaviral disease: frogs with reddened legs may be ill due to some other infection, and frogs with the disease may exhibit other signs such as lethargy and emaciation. It is also possible that frogs can have the disease but show no clinical signs of infection.
Photograph: c. Neill Talbot.
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