Jackson said amphibians are very sensitive to changes in their surroundings, and as the landscape changes so do the species you find on it. For instance, if you have a pond that used to be in the middle of a hayfield and it was abandoned and it grows to forest around the pond, you could see a real change in the species there. Bullfrogs like open sunny ponds. And as trees grow up around these ponds, they became less suited for bullfrogs. And if the pond had toads in it when it was a sunny pond, it might not have them when it becomes a shady pond.
Wood frogs tend to like forested ponds.
They breed early and their tadpoles eat toad eggs. Just as the reasons for the problems are not clear, neither is it clear how fast the problems develop. Scientists don't know. Richmond said biologists have one other suspicion as to why the problems with amphibians are occurring worldwide. And it is the suspicion that perhaps scares them most.