Iowa wildlife experts are looking into a new deer contraceptive that could curb the state's multimillion-dollar-a-year overpopulation problem.

The new, single-dose birth control vaccine would neutralize sex hormones in the famously fertile and polygamous animals. It would result in infertility in males and females.

"It's not something you want anyone or everyone to use," said Dale Garner, wildlife bureau chief at the Iowa Department of Natural Resources. "We want to make sure it's not used willy-nilly in the state."

'We want to make sure it's not used willy-nilly in the state.'—Dale Garner, Iowa Department of Natural Resources

In order to do that, there's a bill before the state legislature aimed at regulating wildlife contraceptives. The proposed legislation would also restrict the use of growth hormones in deer, as well as drugs for sedating animals or treating them for disease.

The contraceptive vaccine, called GonaCon, is being developed by researchers at the U.S. National Wildlife Research Center, a branch of the U.S. Department of Agriculture. It is expected to be submitted to the Environmental Protection Agency in March, said Gail Keirn, a spokeswoman for the research center.

EPA approval pending

The EPA wouldn't likely approve the drug until early 2008, making it the first wildlife contraceptive available for nonresearch purposes.

Researchers say the vaccine, a protein, shouldn't be dangerous for people to eat meat from a vaccinated deer. However, Garner worries about what could happen if people are accidentally injected with the drug.

"What if some people in a neighborhood get a deer down ... and it's kicking or takes a sidestep or a roll and some guy or lady gets injected in the rear end?" he said. "Or if somebody's shooting a dart gun at deer in a park, and it misses an animal and hits a person? Or if a kid picks up an unspent dart and the injection goes off?"

Use of wildlife contraception in Iowa is not a common practice, so far, said Chad Machart, president of the Iowa Whitetail Deer Association. Other vaccines have seemed impractical because they required singling out females for an injection, then finding the same animals again later for a booster shot.

Garner said it could cost anywhere from $300 US to $1,000 to capture and inject each deer with the vaccine, adding that its effect lasts only two years.