WASHINGTON — A remnant of the dinosaur age, the ungainly pallid sturgeon has inhabited the murky depths of rivers for millions of years. Now, because of the way the Missouri and Mississippi rivers have been manipulated since the 1940s, the fish is endangered.
"They've been around since the Jurassic period, but they may not make it to the year 2000," said Kent Keenlyne, Missouri River coordinator for the U.S. Fish and Wildlife Service in Pierre, S.D.
The pale white sturgeon, prized for its eggs that are eaten as caviar, could be saved from extinction but at the cost of less navigation on the rivers, more damaging floods and lower generation of hydroelectric power.
"There are always costs associated with this," said Roy McAllister, who is overseeing a review of the Army Corps of Engineers' master manual for operation of the Missouri River. "It depends on how much people are willing to do."
Once, tens of thousands of sturgeon roamed the rivers. They adapted to the seasonal cycles, spawning during times of increased water flow, like the April and June rises caused by melting snow.
Research shows that the fish, which can grow to 80 pounds, was perfectly suited to the murky Missouri. The river was nicknamed "Big Muddy" because of the sediment and woodland debris that came from erosion and the natural flood cycle.
All that changed after World War II, when a series of six flood-control dams were built along the upper Missouri. The normal cycles of the river were interrupted and migration routes blocked. The sturgeon began an inevitable decline that led to its place on the endangered species list in 1990.
Today, Keenlyne estimates there could be a few thousand sturgeon remaining along their entire range, which stretches 3,500 miles from the Yellowstone River in Montana to the mouth of the Mississippi in New Orleans.
The Fish and Wildlife Service has just released a long-term recovery plan that could affect inland shipping, electric power and flood control.
Already, Midwestern members of Congress are worried about the impact on jobs.
"The human factor, the job element, should be considered when these kinds of issues are on the table," said Rep. Bill Emerson (R-Mo.). "The pallid sturgeon issue should not become another snail darter and or spotted owl."
The sturgeon recovery plan encompasses a wide range of recommendations, including moratoriums on all commercial sturgeon fishing, stocking rivers with captive-bred fish and dumping old trees into channels to form habitats.
The economic impact, however, will most likely be felt in a series of proposals to restore the rivers' natural flow patterns, figure out how to restore the habitat of sandbars and braided channels and remove obstacles to sturgeon migration.
The Fish and Wildlife Service wants to focus initial recovery efforts in six key areas along the Missouri, Yellowstone, Mississippi and Atchafalaya rivers. Officials said these areas would require the least amount of modification.
McAllister said some computer models indicate that making such changes could interrupt navigation along the Missouri, possibly for two months out of the year from Sioux City, Iowa, to St. Louis, and increase the magnitude of floods.
According to a draft economic study by the corps, reductions in river flows could increase costs for shippers of commodities such as farm products, chemicals and oil. Use of barges now can save shippers as much as $9 a ton over alternatives such as railroads and trucks, the study found.
Environmental groups contend that the potential for the corps changing its operation of the Missouri is the only chance in the next 20 years to save the sturgeon and other species, including an endangered plover and tern whose sandbar nests have been wiped out by flow changes.
"It's the biggest decision that will be made on the Missouri River since they built the dams," said Scott Faber of Washington-based American Rivers. "The sturgeons are really the canaries in the coal mine. These alterations in the river are causing harm to all the species."
The economic impact won't be as great on navigation as some may claim, Faber said. He cited a 1992 General Accounting Office report indicating that shipping tonnage on the Missouri has never lived up to the 1944 estimates of 12 million tons a year.
That GAO report showed that commercial navigation peaked at 3.3 million tons in 1977 and has declined every year since. Nonetheless, such economic interests have powerful protectors in the federal government.
"We think this will be a political decision, not a scientific decision," Faber said.
No final decisions have been made on any changes in river operations. McAllister said the corps will produce a draft environmental impact statement this summer and conduct a series of public meetings around the region to determine which alternatives to choose.