HENDERSON, Minn. (AP) — Bruce Nelson was catching frogs for catfish bait last year when he realized something was horribly wrong: Some of the frogs had stumps for legs, and others had as many as four tangled hind legs.
“You see deformed things all the time in nature, but nothing like this,” said Nelson, who made his discovery while catching frogs in a pond near Fisher’s Landing in northeastern Minnesota.
All across Minnesota, into neighboring Wisconsin and South Dakota and in Quebec, scientists and locals are seeing the same kind of grotesquely misshapen limbs, along with frogs with tails, missing or shrunken eyes, and smaller sex organs.
In fact, scientists have had a hard time finding wetlands in Minnesota with no deformed frogs. Most recently, deformed frogs were found in Vermont.
“It scares me,” said Judy Helgen, a research scientist with the Minnesota Pollution Control Agency. “I’m at different levels of getting a chill down my spine.”
Scientists aren’t sure what’s causing the deformities. The theories run the gamut from pesticides to parasites to radiation from ozone depletion, or some combination of factors.
What worries many around the state is whether humans are in danger, too.
“There’s a reasonable assumption that if there’s an external substance influencing amphibian development, it could influence human development,” said David Hoppe, who is on a state-financed team of scientists researching the problem.
So far, little has been discovered. The federal Environmental Protection Agency plans to do its own study.
Students from the Minnesota New Country School in Le Sueur, in the heart of the state’s farm country, first reported the deformed leopard frogs during a field trip to a wetland last year.
They reported their findings to the pollution control agency, then to state lawmakers, and finally went worldwide by putting their information and pictures of the frogs on the Internet.
“When somebody caught a frog without one leg,” 13-year-old Jack Bovee told a state House committee this year, “I thought, `Houston, we have a problem.'”
Cindy Reinitz, the teacher who has become known as “The Frog Lady” since her middle school students made the discovery, said there is at least once person with cancer in every household around the wetland. But scientists have made no direct link between the frog abnormalities and cancer.
A newly created frog hot line has received hundreds of sightings of deformed frogs, from 54 of the state’s 87 counties.
The fact that the abnormalities are widespread suggests that the problem has more than one source, said Hoppe, a herpetologist from the University of Minnesota at Morris.
His best guess is some sort of water pollution, possibly from something airborne. That could come from heavy metals, pesticides or a whole array of things that settle onto the landscape.
In researching some 10,000 frogs this summer, Hoppe said, he found that the most aquatic frogs had the worst abnormalities.
“I was very surprised, startled even,” he said, “because I’ve seen a lot of frogs over the years, and I’ve never seen anything like that.”