The Minnesota Pollution Control Agency's six-year-long search to find the cause of the state's widespread frog deformities appears to have ended. Until this year, PCA researchers were at ground zero of an investigation that involved scientists nationwide. Now the agency's retreat is leaving what some scientists say is a critical hole in the effort to solve the mystery of the deformed frogs.
An image of a deformed frog. To see photos of the research conducted by the U.S Geological Survey, visit the USGS amphibian research site.(Photo courtesy of the USGS)
IN THE SUMMER OF 1995, SCHOOL CHILDREN ON A FIELD TRIP
discovered large numbers of deformed frogs in a farm pond in southwest Minnesota. Ever since then, researchers from the Minnesota Pollution Control Agency have searched for the cause of the problem. PCA staff gathered field data from wetlands across Minnesota every spring and summer.
But this spring, none of the agency's researchers surveyed for deformed frogs. The frog program's coordinator left last fall, and the MPCA has not hired a new one. Now the Minnesota Legislature has indicated it does not plan to continue the program's funding. to the dismay of scientists like Carol Meteyer.
"The amount of contact that I had with that organization during our field investigations was daily," says Carol Meteyer, a wildlife pathologist at the National Wildlife Health Center in Madison, Wis.
For years, field staff for the PCA have been collecting deformed frogs from Minnesota wetlands and sending them to Meteyer.
"They would tell me by cell phone, what sites they were at, what they were seeing, what should they be collecting. Should they get more tadpoles, get more frogs. So there really was a close connection," says Meteyer.
Meteyer says she can still continue her research, but without good data from the ponds where the frogs were collected, drawing conclusions will be more difficult. Meteyer says the MPCA also served as an information clearinghouse for scientists. Now that connection will be lost.
"It is discouraging. MPCA was a real catalyst for bringing everybody together," she says.
SHOULD MPCA BE IN THE RESEARCH BUSINESS?
A PCA staff member who asked that his name not be used says researchers inside the agency are deeply disappointed and discouraged by the frog program's termination. But Minnesota Pollution Control Agency Commissioner Karen Studders defends the agency's pullback.
"It is discouraging. MPCA was a real catalyst for bringing everybody together."
- Carol Meteyer, wildlife researcher
"The Pollution Control Agency is not a research institution. We are a regulatory agency, and our thrust is not research," says Studders. "And what you're asking the agency is something that is outside the normal mission of the agency. We don't have staff on board with those skills."
Studders say the agency did want to continue collecting frogs and water samples for other researchers, but the Legislature would not fund that effort.
But others claim the reason the PCA lost its funding is the agency's lukewarm support for the program. One outside scientist who has worked closely with the agency, and who spoke on condition of anonymity, says managers at the PCA are uncomfortable with the possibility that the deformed frogs indicate a wider problem in Minnesota's environment. In his opinion, PCA managers are glad to be rid of the frog program.
"I think they've been looking for a way out, quite frankly," he says. He calls it a "sad and important loss" that will make finding answers to the deformed frog puzzle more difficult.
FROG RESEARCH IS LOSING STEAM OVERALL
The PCA's move may be part of a wider problem for deformed frogs research. Mike Lanoo of the Indiana University School of Medicine has followed the deformed frogs investigation since it first began. He says that the PCA's disengagment comes as a number of federal agencies also appear to be decreasing their commitment to the investigation.
"There's still interest in this issue, but it looks like any organized, systematic effort to study the problem has gone out the window," Lanoo says. "And it's still a problem. The problem has not gone away, (just) because it's not in the newspapers anymore."
Lanoo says he expects from now on the main investigators of frog deformities will be researchers working mostly in smaller labs with modest funding. He says those scientists realize they're in for a long haul.
Lanoo remains hopeful that scientists will find answers. Although it's taken much longer than anyone expected, he says the investigation has made solid progress. Carol Meteyer of the National Wildlife Health Center in Madison agrees.
"We see our own progress, but I don't think the public sees the amount of distance we've come. I get more excited as the process evolves," says Meteyer.
MPCA Commissioner Karen Studders says her agency is getting out of the research effort into deformed frogs because her agency's mission is to enforce regulations, not conduct research. The MPCA's web site maintains a page about deformed frogs. (Photo courtesy of the MPCA)
RESEARCHERS REPORT PROGRESS IN FINDING CAUSES
One piece of the puzzle appears to be solved. Scientists now have done the experiments necessary to prove that some of the deformities found in wild frogs are caused by parasites. It took several steps.
First, researchers found deformed frogs infected with parasites. Then, they isolated the same parasites from the ponds where the deformed frogs lived. Next, they used the parasites to infect healthy frogs in the laboratory. The healthy frogs developed the same deformities found in the wild. That's convincing evidence that the parasites found in pond water are causing deformities. But that's still only part of the explanation.
Most scientists think parasites are not the only culprits, since the parasites implicated in the experiments seem to inhabit only about one-third of the wetlands harboring deformed frogs. That leaves the deformities in the other two-thirds of the wetlands unexplained.
So researchers continue to investigate another long term suspect - water-borne chemicals. The goal is to isolate a chemical compound from pond water and use it to cause deformities in healthy frogs. But that's harder to do with chemicals than it is with parasites. Parasites are tiny but distinct animals that can be isolated from water with relative ease. It's much more complicated to isolate a chemical.
David Gardiner, a developmental biologist at the University of California at Irvine, believes he's getting closer to that goal. Gardiner has been testing water from Minnesota ponds where deformed frogs have been found, to see if the water contains a kind of chemical known as a retinoid, a naturally-occurring derivative of vitamin A that's known to cause deformities in laboratory animals.
"We have strong evidence that such a chemical exists. That part we have, and the idea is to identify it. It's still a complex mixture," says Gardiner. "There's thousands of chemicals when you begin, and we're down to about a dozen. But you're not there until you're down to one, and it gets progressively more difficult as you get closer and closer to one."
Gardiner says if scientists studying chemicals in laboratories do make a breakthrough, the PCA will have picked a bad time to pull out of the investigation. He says the next step in solving the problem will require more information from the field - exactly the kind of data the MPCA is no longer collecting.