BILLINGS, Mont. — Montana re-opened portions of the Yellowstone River and most of its tributaries Thursday, but it kept a popular stretch of the waterway closed to all recreational activity because of a parasite that has killed thousands of fish.

State officials lifted the closure outright along more than 100 miles of river between Livingston and Laurel.

They kept closed a 51-mile stretch of the Yellowstone in the Paradise Valley. That’s an acclaimed destination for fly fishers seeking trout and where thousands of mountain whitefish died in recent weeks.

Officials allowed rafting and other activities to resume on a 26-mile stretch of river just north of Yellowstone National Park. Fishing remains banned in that area, over worries that trout infected with the parasite could be die if they face additional pressure from anglers.

The closure had effectively shut down dozens of fishing outfitters, rafting companies and other businesses that depend on money generated by the region’s outdoors industry.

State Fish and Wildlife Commission Chairman Dan Vermillion, who also works for a guide service based in the Paradise Valley, said he sympathized with those suffering economic harm but had to keep the river’s long-term health in mind.

Rafting company owner Mike Barlow said it already may be too late to resume his season.

“We’ve lost wedding parties that were booked for this weekend, church groups booked for this weekend. I had hundreds and hundreds of people lined up for early September,” he said.

Barlow’s Wild West Rafting is one of six rafting companies in Gardiner.

He’d been looking forward to August and September potentially being the best months yet in his 22 years with Wild West Rafting. Record numbers of visitors had been pouring into Yellowstone National Park as the park service marks its 100th anniversary.

Barlow, meanwhile, has spent the past two weeks cancelling trips and sending out refunds. Many of the industry’s seasonally-hired guides have left town.

“The town has really shut down. A lot of the restaurants are suffering,” Barlow said.

The 183-mile stretch of the Yellowstone and all waterways that drain into it had been closed since Aug. 19 to prevent the deadly aquatic parasite from spreading.

The unprecedented move came after dead mountain whitefish started washing up on the river’s banks downstream from the national park. Wildlife officials estimate tens of thousands of fish likely died and most sunk to the river bottom.

Most of the Yellowstone’s tributaries also were re-opened Thursday, except for the Shields River and streams that drain into it. Infected fish have been found in the Shields, and Fish Wildlife and Parks Director Jeff Hagener said the agency wanted to protect its cutthroat trout fishery.

State biologists reported finding the parasite blamed for the Yellowstone fish kill in the Jefferson River, part of the Missouri River drainage. The problem was not considered as severe as the Yellowstone, and the Jefferson remains open.

Infected and dead fish have been found in the portions of the Yellowstone that have re-opened. Cooler water temperatures should boost survival rates, after warmer water in August made fish more susceptible to dying, state officials said.

Additional watercraft inspection stations will be set up to make sure people who use the river are properly cleaning their boats and equipment to prevent the deadly parasite’s spread, Fish Wildlife and Parks spokesman Ron Aasheim said.

Biologists will float along the upper section of the river on Sept. 6 to inspect it and determine if the fishing ban can be lifted, officials said.

Smaller numbers of other fish species including trout have been killed. Fish and wildlife officials have said the rate of fish dying appears to have eased in recent days. They’re hopeful it won’t affect trout as heavily as it did whitefish, sparing a fishery that’s both ecologically and economically important.

The closure order for the Yellowstone expires after 120 days, on Dec. 17, barring further action from wildlife officials.

Gov. Steve Bullock on Monday declared an “invasive species emergency” that allows Montana to spend up to $15.4 million on worker retention grants and other programs.

Biologists say outbreaks of the parasite are possible in future years now that it’s been established in the Yellowstone.


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