Video by Eric Keith

A net dipped gently into the cold, dark waters of the Missouri River. About 75 wiggling pallid sturgeon fingerlings thrashed, then descended to their new home Wednesday.

The fingerlings were raised at Blind Pony Fish Hatchery at Sweet Springs, Mo., had grown to 6 to 8 inches long and were ready for release, said Darby Niswonger, a Conservation Department resource staff scientist.

Except for an occasional fish leaping out of the water and flocks of geese winging through the cold sky, it was a quiet day to work on the river.

Mrs. Niswonger, Thomas Huffman and Ryan Dirnberger launched a work boat with a 100-gallon tub at the Jentel Bres boat ramp. After filling the tub with river water, 600 of the Blind Pony fingerlings were transferred.

Mrs. Niswonger cranked up the engine and headed out into the Missouri, searching for a slow, shallow spot close to the bank. Mr. Dirnberger tossed an anchor over the side as the boat slipped into the chosen spot. After jotting a GPS location on the side of her hand, the scientist and Mr. Dirnberger began to shift the pale, squiggling fingerlings out of the boat.

Each fingerling was marked with liquid plastic on its snout and had its fifth scute (a bony side protrusion) snipped.

Mrs. Niswonger said the color tells what year the fish was spawned, and the snipped scute is a back-up for identifying sturgeons that come from the hatchery, versus those born in the wild.

"We know that they are surviving, but don't know if they are reproducing," Mrs. Niswonger said.

Pallid sturgeons, with their shovel snouts, can grow to be about 6 feet long and weigh about 80 pounds. The fish can live for 60 years in the muddy waters of the Missouri River.

"But something's out of balance in the Missouri River ecosystem because these fish have been disappearing," Mrs. Niswonger said. "It's a warning for all of us that the system's not doing well."

The pallid sturgeon was declared an endangered species in 1990. The Army Corps of Engineers is required to create shallow water habitat, propagate the species and restock the river.

The corps contracted with Missouri to raise the fingerlings and study the river population, Mrs. Niswonger said. The Blind Pony hatchery was the first to successfully propagate the species, back in 1992, she said.

Other state and federal programs have been adding pallid sturgeon to the Missouri River since 2001.

After returning to the Jentel Bres ramp, the three conservationists headed south to collect information about pallid sturgeons on another section of the river.

Marshall White can be contacted

at marshall@npgco.com.