Minnesota has had probably more reports of malformed frogs than other states. This may be due to increased public awareness of the issue and not necessarily because our numbers of malformed frogs are higher. However, biologists with nearly 40 years of experience in surveying frog populations here have never seen abnormalities to the extent they are present in the state now. This appears to be a recent phenomenon in Minnesota.
-from the MCPA Deformed Frogs FAQ
(courtesy Sailor Tork, who's done her homework.)