Three environmental groups have filed a lawsuit trying to stop the planting of genetically-modified crops at wildlife refuges in the Southeast, including one location in South Carolina. The lawsuit covers 25 refuges across the Southeast that plant the crops.

Right now, Santee National Wildlife Refuge on Lake Marion allows farmers to grow corn on roughly 175 acres, with much of it meant to feed ducks and geese that pass through the park. The Fish & Wildlife Service, the agency that runs the nation’s wildlife refuges, does not make money off its arrangement with farmers.

However, the Center for Food Safety says it is concerned about the effects of that farming and is suing to stop the practice. ”These crops promote overuse of herbicides,” staff attorney Paige Tomaselli said, ”Since most genetically-modified crops are herbicide-tolerant, the farmers can indiscriminately douse the crops with as much herbicide as they want… And this can affect wildlife, biodiversity, and humans who visit the refuge.”

The lawsuit demands an end to the practice until the Fish & Wildlife Service completes an environmental impact statement. However, Fish & Wildlife spokesman Tom MacKenzie said the agency already goes beyond the restrictions for traditional farms: allowing fewer pesticides, creating “buffers” between the crops and waterways, and requiring farmers to rotate crops.

“We’ve been in the cooperative farm business for years and we’ve utilized genetically-modified crops just like most of the other farmers in America are doing,” MacKenzie said.

Santee NWR was created in 1941 to provide a haven for waterfowl after the Santee River was dammed to create Lake Marion. Farming is relatively small there, but officials work with farmers to plant millet and sorghum, with 25 percent of the crop reserved for migrating waterfowl, such as geese and ducks. After a harvest, the field is flooded, and the leftover grain provides a source of food for the birds.

However, Tomaselli disputes that the crops provide extra food. “These crops are pushing out the native grasses that were originally there to feed the migratory birds,” she said, “As long as we’re perpetuating the farming on the refuges, the native grasses and other plants cannot return.”

Santee Refuge Manager Marc Epstein said the number of waterfowl has recently started to decline at the site. He said the crops offer a way to maintain the population. However, the rising costs of fertilizer, fuel, and seeds are slowing farmers down, “It’s costly for us to do these programs,” he said.

Tomaselli says, while the group is pushing to stop the planting of genetically modified crops, it wants to eventually stop any type of farming in wildlife refuges. The group has successfully stopped the practice in the Northeast after two lawsuits in Delaware, and is now looking at ending farming in the Southeast, as well.

MacKenzie said that would have a negative impact, “For 25 out of our 128 refuges, we currently believe that farming helps wildlife.”

The complaint was filed in a federal court in Washington, D.C. Two other environmental groups, Public Employees for Environmental Responsibility and Beyond Pesticides, are also involved in the lawsuit.