U.S. National Wildlife refuges often use farming to help restore natural habitat.

But some of the crops grown on these protected lands are genetically modified — and that’s raising concerns among organic farming advocates and others.

Prompted by a lawsuit, the U.S. Fish and Wildlife Service over the next few months is conducting an environmental review of the use of genetically modified crops on wildlife refuge lands, including those in Nebraska, Missouri, Kansas and Iowa.  

“When we turn it into farming the farmer is out there controlling the weeds on our behalf, he’s doing it for his crop, but by the end of three years most of that weed seed in the ground is gone and then we come back and seed it back with native grasses,” said Gene Mack, project leader for the Rainwater Basin Wetland Management District.

The district maintains wetlands throughout 17 counties in south-central and eastern Nebraska where millions of birds — from ducks to sand hill cranes — stop along their migratory patterns.

About 60 percent to 70 percent of the land being farmed in the National Wildlife region that includes Nebraska and Kansas is seeded with genetically modified “Roundup ready” seeds. This means the crops can withstand spraying of the weed-killing herbicide Roundup.

Tom Koerner is collecting public responses for the environmental assessment, which he said looks to answer many questions. 

“Is this a tool that’s appropriate to use on refuges? Are there other things that could be used that would accomplish the same objectives? That’s what we’re reviewing, not the farming itself, but this new technology of GM soybeans and corn,” he said.

But Charles Benbrook, chief scientist at the Organic Center in Boulder, Colo., said using genetically modified seeds can lead to adverse consequences.

“This will accelerate the emergence of weeds that are genetically resistant to Roundup and not controlled by applying it and in that case there can be proliferation and spread of weeds as a result of these crops, he said.

Benbrook said if wildlife refuge managers were to contract with farmers who are willing to grow with little or no pesticides it would be better on the biodiversity.

The U.S. Fish and Wildlife Service is inviting public comment on draft Environmental Assessments through Feb. 14 for the Midwest Region that encompasses Missouri and Iowa, and through March 4 for the Mountain-Prairie Region that includes Nebraska and Kansas.

Click here for the draft assessments for the Midwest Region and the Mountain Prairie Region.