The closure of almost 200 miles of the Yellowstone River and its tributaries flowing through Montana is being described as “unprecedented” by officials of the State’s Department of Fish, Wildlife, and Parks, reports Reuters.
According to the FWP notice issued on August 19, the closure is defined as starting at Yellowstone National Park’s northern boundary at Gardiner to the Highway 212 bridge in Laurel. The closure of the river will remain in effect until temperature, water quality, and fish mortality has improved.
The WFP found over 2,000 dead whitefish along stretches of the river and further investigation revealed that as many as 20,000 or more fish were dead, along with some rainbow and Yellowstone cutthroat trout. Officials feel that the closure is necessary to protect a state resource and the economy it sustains.
The disease infecting the fish is caused by a microscopic parasite called Tetracapsuloides bryosalmonae. The parasite causes proliferative kidney disease (PKD) a rare but very serious condition found in two isolated spots in Montana over the past two decades. The disease has a mortality rate of 90 to 100 percent.
On Thursday, two decontamination stations were set up along Interstate 90 both east and west of Livingston. Anyone who has used the Yellowstone for recreational purposes will be required to stop by these wash stations. The parasite does not pose a risk to humans, but it is important to nip the outbreak in the bud.
“A threat to the health of Montana’s fish populations is a threat to Montana’s entire outdoor economy and the tens of thousands of jobs it sustains,” said Gov. Steve Bullock, adding that the state would do whatever it takes to stop the disease from spreading to other rivers.
According to KBZK.com, there have been outbreaks of the disease in Washington, Oregon and Idaho recently.
An increase in the prevalence and severity of PKD outbreaks has been observed over the past few years, and this is being explained as being a result of environmental changes which are likely to cause PKD outbreaks in more northerly regions as warmer temperatures promote disease development.