Barge traffic could grind to a halt on a 250-mile stretch of the Missouri River, after the U.S. Fish and Wildlife Service ruled last week that two endangered species of shorebirds cannot be moved to accommodate the release of water from two dams in South Dakota. The U.S. Army Corps of Engineers planned to release water from the dams to raise the level of the drought-stricken river. Doing so would have required relocating piping plovers and least terns, which nest on sandbars and islands in the Missouri, but the move was nixed by the USFS in the interest of protecting the birds. That means barges are up a creek; experts said there would be essentially no barge traffic between Kansas City and Sioux City unless heavy rains swell the river. American Rivers praised the decision for protecting the species, but the barge industry said the low water levels raised concerns about the possibility of oil spills as boats ground on the river bottom.