"The Mississippi River is notoriously unforgiving. It can be a dangerous place," said Lt. Commander Patrick Clark of the U.S. Coast Guard. "A GPS can tell you your previous navigational route -- but it can't reveal what may lie in your path the next time down the river."

Bass tourneys are held almost every summer weekend on the Mississippi, with impact on both safety and the environment essentially uncharted, due in part by multiple jurisdiction between states bordering the river, the U.S. Fish and Wildlife Service charged with protecting natural resources in the refuge, which encompasses a great deal of the river and its backwaters, and the U.S. Coast Guard, which is responsible for maintaining the 9-foot-deep navigational channel between the red and green buoys on the main river.