Global Warming is Real, and the Yellowstone River is Proof

Yellowstone River Fishing

With our National Park system celebrating its 100th birthday in just a few days, the parks themselves have been receiving more attention than usual. Although much of the social media buzz and travel advertising has a positive impact on the parks, it doesn’t always inform visitors of the vulnerability that these amazing spaces deal with.

After first laying eyes on Yellowstone as a 7th grader, I felt just how special these lands were, not only to us as human beings but our entire ecosystem as a whole. It’s the earth’s most vulnerable places such as Yellowstone, where even the slightest changes in the ecosystem can have rippling effects on the environment. Unfortunately for us, the changes that are taking place can’t be categorized as “slight” whatsoever.

A recent breaking news event was published by the National Wildlife Federation, which shared a detailed account of a fish die-off in the Yellowstone River. We are all free to form our own opinions on the matter, while also respecting to listen to the reasoning behind them.

The Build Up

On August 19, 2016, Montana officials closed down a significant portion of the Yellowstone River to all recreational use in response to the die-off of thousands of fish.  Throughout Montana world glass fishing opportunities still abound, and anglers continue to travel to the state to experience some of the best fishing in the world.  However, the closure of the Yellowstone River is already having dramatic impact on the local community and economy.  This local disaster is representative of what scientists suggest will become the norm on most Montana rivers if nothing is done to address the effects of climate change.

The Yellowstone River Die Off

In mid-August, fishing guides and other river users began noticing an unusual number of dead whitefish in the Yellowstone River downstream from Yellowstone National Park.  Staff from the Montana Department of Fish, Wildlife and Parks have since confirmed the remains of more than 3,000 whitefish, two rainbow trout, one Yellowstone cutthroat trout and several suckers.  Department officials estimate the total number of fish killed is likely in the tens of thousands.

The cause of the Yellowstone River die off is a widespread outbreak of proliferative kidney disease (PKD).  This disease is caused by a microscopic parasite distantly related to jellyfish that causes enlargement of the kidneys and a deficiency in the oxygen-carrying capability of the blood.  Research shows that mortality in areas the first year of an outbreak can range from 20 to 100 percent.  Up to this point, outbreaks of PKD have been pretty rare outside of Europe.  In the US, they have occurred in Idaho, Washington, and Oregon, and the parasite that causes the disease has been found at two isolated spots in Montana.

In light of this outbreak on the Yellowstone River, the Montana Department of Fish, Wildlife and Parks has closed all recreational use of 183 miles of the Yellowstone River and all of its tributaries from the border of Yellowstone National Park downstream to the City of Laurel.

Yellowstone River


Recent coverage:             Billings Gazette article

Bozeman Chronicle article

Elevated Water Temperatures and Climate Change in Montana

This year, Montana’s rivers and streams have experienced extremely low flows and high temperatures.  Currently, the Yellowstone River at Livingston is running at 1,930 cubic feet per second—only 300 CFS above its all-time low.  In addition, higher ambient air temperature trends are leading to higher stream temperatures as well.  This combination of low flows and high water temperatures puts added stress on coldwater fish species such as trout and whitefish.

The Montana Department of Fish, Wildlife and Parks has been proactive in its management of the state’s rivers during periods of low flows and/or high water temperatures.  The agency has a protocol to close rivers to recreational fishing for part or all of the day if conditions become too extreme.  Currently, in addition to the Yellowstone River closure prompted by the PKD outbreak, seven rivers are under “hoot owl” closures that prohibit fishing after 2pm.  Two other rivers (Bighole River and Jefferson River) are under 24-hour closures.

In addition to addressing the current situation, Fish, Wildlife and Parks has already started planning for ongoing management under climate change.  The Department has a section on climate change in its Statewide Fisheries Management Plan that lays out a plan to continue to use closures and to reduce the stressors caused by the changing climate.

Many scientists believe that climate change is having an impact on rivers and streams, and trends show snowpack is declining and spring runoff is happening earlier across the nation.  The dangerously low flows and high temperatures currently facing Montana rivers are consistent with the effects of climate change, and representative of what most scientists expect will be the norm in the years ahead.

Proliferative Kidney Disease and Climate Change

The impact of pathogen invasions on fisheries in general depends on a myriad of factors.  If the habitat is good, environmental conditions are optimal, and fish are healthy, the pathogen invasion may have little or no impact.  But low flows and high water temperatures lead to poor environmental conditions that impact the health of trout and whitefish and make them more susceptible to pathogens.  Climate change has been identified by fisheries biologists as a fact (Chiramonte et al 2016).

In addition to generally weakening fish, high water temperatures also increase the virulence of PKD itself.  An increase in average temperatures allows for faster parasitic spore development of PKD in the host and a longer timespan for PKD to develop.   Research shows that higher water temperatures have led to a higher prevalence of PKD in wild salmon in northern Europe.  (Sterud et al 2007).  In fact, scientists have specifically cited PKD as a disease that will be aggravated by climate change. (Tops et al 2009).

Economic Impact

Closing the Yellowstone River is the right thing to do, and Fish, Wildlife, and Parks authorities has been commended by most stakeholders for taking decisive action.  It is imperative that this world famous fishery be conserved, and the closure will help prevent the spread of PKD to other rivers in the area.  But make no mistake, the recreation closure will have a significant impact on the economy of the area.  Outfitting and guiding on the river is a big part of the area’s economy, and reduced fishing and floating on the river will undoubtedly impact local hotels, restaurants, and other tourist-related businesses.

Dying fish in Yellowstone

The local economic hardship that is occurring as a result of the Yellowstone die-off are representative of what experts predict will happen on many Montana rivers if nothing is done to address climate change.  A recent study prepared for the Montana Wildlife Federation found that climate change impacts are projected to reduce angling days by one-third and result in economic loss of 1,800 jobs and $49 million in labor earnings.

Outdoor recreation accounts for $6 billion worth of economic activity each year in Montana.  Climate change is a very real threat to this economy, and the current experience on the Yellowstone River should stand as a cautionary note to elected officials.

Without placing blame, it’s hard to deny that a warming trend within our environment isn’t occurring. From decades of human activity, to a natural global event, change is happening at a staggering rate. As the current stewards of these lands, we must prepare for these oddities and formulate a plan of action to reduce any further pollution. As the research indicates, large populations of human beings depend on these resources for their livelihood and it’s our responsibility to preserve what belongs to each and every one of us.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.