Tentative agreement reached in dispute over endangered fish

Wildlife advocates reached a tentative agreement with the U.S. government in a legal dispute over an endangered fish in the Yellowstone River along the Montana-North Dakota border.

The case centers on a proposed irrigation dam and fish bypass northeast of Glendive. Supporters of the $59 million project say it would allow pallid sturgeon to reach upstream spawning grounds that they've been unable to access for decades.

U.S. District Judge Brian Morris blocked construction of the project in September. That came after the Defenders of Wildlife and the Natural Resources Defense Council sued the U.S. Army Corps of Engineers in February, arguing there was no proof the fish bypass would work.

Attorneys for the two sides said in a court filing that they planned to finalize by Dec. 30 an agreement that would allow the matter to move forward while the lawsuit is pending.

Terms were not disclosed, and attorneys in the case declined to give further details. In his September ruling, Morris said the government needed to provide more evidence for the anticipated success of the bypass before he could decide if it would help or hurt sturgeon.

Pallid sturgeon are known for their distinctive shovel-shaped snout and can live 50 years, reaching 6 feet in length.

The dam would replace an existing rock weir used to divert irrigation water for more than 50,000 acres of cropland in Montana and North Dakota.

The 125 sturgeon that inhabit the lower Yellowstone have been essentially trapped downstream of the rock structure since it was built in 1905. At least one female fish managed to swim around the structure during high water last year, but that was considered a rare occurrence.

Pallid sturgeon was listed as an endangered species in 1990. Believed to date to the days when Tyrannosaurus rex walked the Earth, the species has declined sharply during the past century as dams were built along the Missouri River system.

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