Paying deerly

Pesticides could be linked to ungulate mutations



Even on an icy Montana morning, 71-year-old Judy Hoy feels compelled to stop her car on the side of the highway and pull out the blue metric ruler that she carries wherever she goes. Then she measures the facial bones of a dead white-tailed deer.

"I just stop on the road," she says. "Everybody thinks I'm nuts."

Hoy has always loved animals. Her first word at nine months was "Buff," she says, her family's dog's name. "My mom and dad were not happy."

Hoy has a hard time calculating the number of animals she's cared for over the years. It's an array of geese, goats and squirrels, along with crows, owls and eagles, all of which she nurses back to health at her wildlife rehabilitation facility south of Stevensville. She feeds baby birds with plastic medicine droppers, mends the broken limbs of squirrels and applies natural ointments to wounds.

Her husband, Bob Hoy, worked as a Montana Fish, Wildlife and Parks game warden before he completely retired in 2002. In the 1990s, he brought home road-kill for Judy to feed to her hungry carnivores. In 1996, the Hoys began noticing that the deer Bob brought home appeared to have genital malformations. Some were missing scrotums. Testes appeared strangely aligned, one in front of the other. Penises suddenly appeared smaller. They also saw that deer teeth stuck out and failed to align properly.

Curious, Judy and Bob began what would become a 14-year study in which they examined more than 1,000 deer, elk, antelope, sheep and goats. They worked with Gary Haas, a Florence taxidermist who had also spotted bone structure changes in hunter-harvested game. Dr. Pamela Hallock Muller, a University of South Florida professor and Hoy's sister, signed on to lend her technical expertise. Their findings were published in this month's issue of the journal Wildlife Biology in Practice.

Missoula news
  • Photo courtesy of Judy Hoy
  • The pronounced under-bite of a white-tailed deer, which Judy Hoy fears may be just one result of pesticides.

Five percent of the 227 white-tailed fawns that Judy Hoy examined between 1995 and 2000 had under-bites. That number spiked to 52 percent of 330 fawns between 2001 and 2010.

Hoy, who has no formal scientific training, surmises that pesticides in the environment are disrupting the animals' hormonal systems.

In 2008, the Montana Department of Agriculture found pesticides in 25 of 46 groundwater samples and nine of 10 surface water samples taken from the Bitterroot Valley. The herbicides prometon and atrazine were detected most frequently. The Environmental Protection Agency classifies prometon and atrazine as potential endocrine disruptors, part of a family of chemicals that scientists say trigger hormonal changes in people, animals and insects.

In 2007, because of health concerns, the European Union banned atrazine. The herbicide remains legal in the U.S. as the EPA reviews scientific claims that assert, among other things, that pregnant women exposed to even very small amounts of atrazine—one part per billion—have babies with low birth weights. The Montana Department of Agriculture found even smaller amounts of atrazine—less than one part per trillion—in Bitterroot groundwater. That's well below federal drinking water standards for people.

In 2004, in response to Hoy's concerns, Montana FWP wildlife laboratory supervisor Neil Anderson checked to see if there were other reports of malformations in wildlife. He said then–and continues to say now—that he's not finding a significant disruption in the animal kingdom. "There's no doubt that if there's excessive use of chemicals and there's a proliferation of pesticides in the environment, in certain cases it can cause some problems," Anderson says. "I think that's been well documented in amphibians and a few other species. Now, is it affecting the white-tailed deer, mule deer or other ungulates in Montana? I don't know that we can come out and say that."

University of Montana wildlife biology professor Kerry Foresman echoes Anderson. "Field biologists working around the state have not noticed an increased incidence of malformations that Hoy suggests she is finding," Foresman says. "We'd know about it."

Foresman says that because there's a lot of variability in nature, the malformations Hoy is charting might result from natural processes, anomalies or injuries, especially in the case of road-kill. "There's a lot of asymmetry in animals, in humans," he says.

Hoy isn't the only one decrying the dangers of pesticides and herbicides. Theo Colborn, president of the Colorado-based Endocrine Disruption Exchange, for years has called on regulators and legislators to beef up pesticide oversight. Colborn says scientists know compounds like atrazine make people and animals sick, yet "everyone ignores it."

Legislation is in the works that could curb the impacts of hormone-altering chemicals on people and wildlife. Part of the problem now, Colborn says, is the fact that agencies like the EPA aren't incorporating proven science into regulatory decisions. The Endocrine Disruptor Screening Enhancement Act of 2011, now before Congress, would change that by streamlining communication between researchers at the National Institute of Health and the EPA. It would also let the EPA curb the use of biologically disruptive chemicals.

Judy Hoy faces challenges in getting her work to be taken seriously. Still, she says, she's got proof that animals are being harmed: It's all here, she says, as she points to the hundreds of photographs she's collected of malformed deer, elk and antelope.

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