Pallid Sturgeon Reproduction Confirmed

Pallid Sturgeon Reproduction Confirmed
FIRST REPRODUCTION OF PALLID STURGEON IN LOWER MISSOURI RIVER IN DECADES IS CONFIRMED BY FISH AND WILDLIFE SERVICE

The first known reproduction of the pallid sturgeon in the Lower Missouri River in at least the last 50 years has been confirmed by U.S. Fish and Wildlife Service biologists, who point to the startling discovery as evidence that the fish, whose ancestors date to the days of the dinosaurs, may have a better chance at recovery than previously believed.

"This remarkable news is more than just a testimony to the need to conserve habitat in order to pull an endangered species back from the brink of extinction," Secretary of the Interior Bruce Babbitt said. "It speaks eloquently for the need to restore some natural flows to rivers so theyre more than just dammed and channelized flood control projects sluicing fresh water toward the sea. When the Edwards Dam was removed from the Kennebec River in Maine, Atlantic salmon were seen back in that stretch of river almost immediately. When we let the Big Muddy be the Big Muddy, suddenly on of Americas historic and most endangered gamefish is spotted spawning in nature once again."

"This is wonderful," said Steve Krentz, leader of the Pallid Sturgeon Recovery Team in Bismarck, North Dakota. "Until these tiny sturgeon specimens were found, the only young pallid sturgeon we have seen were products of hatchery spawning operations."

The fish, which can attain a weight of 100 pounds, a length of 6 feet and which have a lifespan of 60 years, have been listed as an endangered species since 1990, indicating a concern that the species was headed for extinction.

Aside from the sturgeons importance as a natural inhabitant of the Missouri and Mississippi River systems, the pallid sturgeon has economic benefits as some anglers consider it one of Americas premier gamefish. Eventual full recovery could mean that the sturgeon would be considered for removal from the endangered species list and would again be available to sportfishing enthusiasts.

The sturgeon is also considered an indicator species whose abundance and distribution are directly related to the quantity and quality of suitable habitat and river hydrology. That these specimens were collected at a habitat restoration project on a unit of the Big Muddy National Fish and Wildlife Refuge indicates that efforts to put back some of the 500,000 acres of habitat lost to channelization can produce dramatic results.

Jim Milligan, project leader for the Fisheries Resources Office in Columbia, Missouri, said the specimens were found along a restored sandbar in a side channel of the Lower Missouri River that had been cut by the flood of 1993 and expanded to a chute-island-sandbar complex by more flooding in 1995 and in 1996. It is the first new habitat of its kind the river has been allowed to create in more than 50 years.

"We acquired the land for the Refuge and gave the river some freedom to re- create some lost habitat through natural processes of erosion, deposition and succession," Milligan said.

"And the area became nursery habitat for juvenile pallid sturgeon. The most significant aspect of this find is that it clearly demonstrates that we can use the rivers energy to restore habitat for the benefit of threatened, endangered and declining fish species. More than 40 other Missouri River fish species have also been documented using the restored habitat."

Pallid sturgeon populations began to drop with the advent of dams, and also when their habitat was altered from shallow, silty rivers with sand and gravel bars to deeper clear channels favored by commercial river traffic. The side channel where the sturgeon were found is not a part of the navigation channel.

An adult pallid sturgeon is a rare find today in any segment of the Missouri River system. In the early 1990s, the Service and its state partners began a hatchery reproduction program and stocked the Missouri River with at least 3,000 hatchery sturgeon to keep the species alive.

"We know the fish found in Missouri are not the result of our stocking efforts," said Steve Krentz, leader of the Pallid Sturgeon Recovery Team in Bismarck, North Dakota.

"The juvenile fish we placed in the river were 8 to 10 inches long and the specimens collected in August were less than an inch long."

Pallid sturgeon historically inhabited rivers and tributaries in Arkansas, Iowa, Illinois, Kansas, Kentucky, Louisiana, Missouri, Mississippi, Montana, North and South Dakota, Nebraska and Tennessee. Some sturgeon still inhabit some of those areas, Milligan said, but the populations are far below what they were in the 1950s and 1960s.

The Missouri Department of Conservation lists the pallid sturgeon as exceedingly rare and confined to the Missouri and Mississippi Rivers penetrating only a few miles into the Mississippi upstream from the mouth of the Missouri. The species is somewhat more abundant in the Missouri River upstream of Iowa, but nowhere in its range is it common.

Unlike such finny freshwater companions as the trout and bass, the pallid sturgeon is a homely specimen. It is distinguished by pale, bony plates instead of scales, has a reptile-like body, sucker-type mouth and large whisker-like growths that help it sense its surroundings. It is similar in appearance to the shovelnose sturgeon but is much lighter in color, has smaller eyes and a longer and sharper snout.

The U.S. Fish and Wildlife Service is the principal Federal agency responsible for conserving, protecting and enhancing fish, wildlife and plants and their habitats for the continuing benefit of the American people. The Services manages the 93-million-acre National Wildlife Refuge System comprising more than 500 national wildlife refuges, thousands of small wetlands and other special management areas. It also operates 66 national fish hatcheries and 78 ecological services field stations. The agency enforces Federal wildlife laws, administers the Endangered Species Act, manages migratory bird populations, restores nationally significant fisheries, conserves and restores wildlife habitat such as wetlands, and helps foreign governments with their conservation efforts. It also oversees the Federal Aid program that distributes hundreds of millions of dollars in excise taxes on fishing and hunting equipment to state fish and wildlife agencies.

-FWS-

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