Levels of this type are often found in agricultural areas as a result of using crop fertilizers, the authors said. When exposed to them, some tadpoles and young frogs reduced their feeding activity, swam less vigorously, experienced disequilibrium, developed physical abnormalities, suffered paralysis and eventually died. And problems such as that, Blaustein said, may go even further. But these flukes have been around forever and we never observed the level of problem we're now seeing with deformed frogs. One thing we know is that these flukes live part of their life cycle in a snail.
Snails eat algae.
And higher levels of nitrogen-based fertilizers can cause increased algal growth, increasing the snail populations. It means that the Earth's ecological systems work in a delicate balance and that seemingly trivial impacts in one area can become magnified as they ripple through the ecosystem, with unintended results or consequences that are difficult to predict and sometimes frightening in their scope. What's less clear, Blaustein said, is exactly what insult, or combination of them, killed these animals, or caused their diseases and deformities. Or, he added, which species will be the next to fall. Good quality digital color images to illustrate this story are available.