National Geographic News
Picture of an angler fishing in Montana

An fisherman in Montana enjoying the river.

Photograph by Jeff Hornbaker, Corbis

Ben Jervey

for National Geographic

Published September 18, 2013

This month, anglers who flock to Montana in search of their own authentic A River Runs Through It experience are out of luck. On September 4, the Blackfoot River, centerpiece of Norman Maclean's beloved story (and its film adaptation that gave the entire fly-fishing industry a boost in the early 1990s), was closed to fishing by officials from Montana Fish, Wildlife, and Parks. They cited "an effort to protect fish from the stress of low stream flows." (The river has since been reopened to fishing, but drought conditions remain.)

Such river closures have become more common in recent years, in Montana and beyond. They've become necessary as coldwater fish populations struggle to deal with low flows and warmer waters, symptoms that scientists link to the rising global temperatures brought about by climate change.

Last year, for instance, stretches of the Madison, Gibbons, and Firehole Rivers—all prized fishing destinations in the Yellowstone region—were closed in August. Scientists and anglers are in agreement: Climate change is already impacting the sport of fishing, and it's likely to get a whole lot worse.

"We've seen huge shifts here in Montana," said Todd Tanner, a lifelong fisherman who spends 200 to 250 days a year on the water, and who has been living in Montana for over three decades.

"Over the last 20 or so years, we're seeing this litany of shifts in weather patterns, and with them, a steady degradation in many of our rivers," said Tanner. "It's directly related to the snow going early, then to warmer springs and summers."

A few years ago, Tanner started the nonprofit, nonpartisan advocacy organization Conservation Hawks, and he argues that fishermen are the best equipped to see firsthand the impacts of climate change. "You can't be out fishing for trout or bass around here and not notice the change," he said.

Swimming Upstream

A new report, published September 4 by the National Wildlife Federation (NWF)—one of the country's largest environmental groups—backs up the anecdotal evidence and explains the variety of threats that climate change poses. Besides the closures themselves—which are typically the result of droughts and earlier than normal melt of alpine snowpack—many rivers are simply getting warmer. According to the NWF report, half of the major American rivers surveyed in a 2010 study experienced "significant warming trends over the past 50 to 100 years."

Fish are sensitive to temperature, explained Jack Williams, a senior scientist with the conservation group Trout Unlimited and a co-author of the NWF report, who describes a massive geographical shift in fish species already underway. "Already, native trout have been pushed around," Williams wrote in an email.

"Non-native species are pushing up from downstream and have sent the native trout into the higher elevation streams," Williams explained. "Unfortunately, these streams are going to be hard hit as wildfire, drought, and increased storm intensities hit these isolated high-elevation areas hard." (See "Amid Drought, Explaining Colorado's Extreme Floods.")

"In the Southwest," said Williams, "the evidence is in your face each time you survey a stream." Small streams in New Mexico, home to Rio Grande cutthroat, Gila, and Apache trout, are particularly susceptible to temperature increases.

Making things even worse are the wildfires, which Williams says the Southwest is seeing "at scales that we have not seen before." Wildfires rip through trout habitat, and the increased runoff that results when the riparian areas burn eventually leads to siltation effects. "It's a killer one-two punch in these small streams," said Williams.

Across the country in New England, coldwater rivers and streams are similarly threatened. In July 2011, Eric Orff, then a New Hampshire fish and game commissioner, was stunned to find water temperatures of over 80 degrees Fahrenheit (27 degrees Celsius) in Indian Stream, "a wonderful, classic trout stream in prime fishing season." According to Orff, the waters were so warm that the trout left, heading for the colder, deeper pools in the Connecticut River.

"So here you are as far north as you can go in New Hampshire," said Orff, "literally looking into Canada, and you have a stream that was fatal to brook trout."

The warming trends are only getting worse. Doug Inkley, a senior scientist at the NWF, points to a study quoted in the group's report. "The science is telling us that in the lifespan of a child born today, 50 percent of the habitat suitable for coldwater species of fish will no longer be suitable for them."

Another study anticipates that brook trout, the official state fish of Virginia, will be gone from that state's rivers entirely by mid-century, due mostly to warmer and more oxygen-depleted streams. Williams co-authored yet another study that predicted a further 77 percent decline in brook trout habitat nationally by 2080, and a 58 percent loss for cutthroat.

Impacts Beyond Coldwater Species

It's not just coldwater species—the trout and salmon, for instance—that are struggling to adjust. In 2005, the first large-scale die-off of smallmouth bass was witnessed in the Susquehanna River. The culprit: a bacterial disease called columnaris that, according to Williams, "becomes a problem and highly contagious at warmer temperatures, and so is becoming a problem associated with climate change."

Since that first event, these summer die-offs have become the "new normal" in the Susquehanna, and outbreaks are being reported with increasing regularity all across the country.

Lake populations, too, are reeling in this new normal. Temperatures in the Great Lakes, where native species like lake trout, whitefish, walleye, catfish, and sturgeon are popular prey for sport and commercial fishermen, have increased nearly 5 degrees Fahrenheit (nearly 3 degrees Celsius) over the past three decades. Even if these temperate water species can deal with some warming, the higher temperatures bring another risk: an invasion of sea lamprey. (See "Busting 5 Myths About Water Levels on the Great Lakes.")

Lamprey survive by latching onto a host fish and sucking its blood. They also grow larger and lay more eggs in warmer waters. The bigger, hungrier parasites are already wreaking havoc on the fisheries of the Great Lakes, explains Inkley, and the invasive species is only going to be harder to control as waters continue to warm.

On Thin Ice

Warmer, shorter winters don't only mean earlier snowpack melt—which throws off the norms in the coldwater streams in the West—they can also keep ice fishermen off the lake entirely. The obvious reason: If prized ice fishing lakes don't ever freeze to safe levels, or if they freeze later and thaw earlier, opportunities to drill a hole and drop a line become fewer and farther between.

Jason McKenzie's family has owned and operated Suds N' Soda, a convenience store and purveyor of fishing gear in Greenland, New Hampshire, for half a century. For the past few years, sales of ice fishing bait and equipment have been suffering. According to McKenzie, two-thirds of their ice fishing inventory went unsold in 2010, and sales have been way off in the years since.

"We've had to adjust our inventory since winter and ice fishing went away five years ago," McKenzie said. "We just can't count on a New Hampshire winter to provide us with ice fishing business like we used to."

Angling: An Industry at Risk

All of these impacts of climate change—the warmer streams and earlier melts; the droughts, floods, and wildfires; and the bacterial disease and invasive species—add up to a lot fewer opportunities for anglers to cast a line. And that means that the business of fishing is also taking a hit.

Craig Mathews runs Blue Ribbon Flies out of West Yellowstone, Montana. He's also something of a legend in fly-fishing and environmental circles, winning Fly Rod and Reel's Angler of the Year Award in 2005 and co-founding 1% for the Planet with Patagonia's Yvon Chouinard in 2001. Mathews says that the past several years have been rough on the area's rivers, and that the changes definitely impact his business.

"Last year we were off close to 5 percent in sales," he said, noting that he doesn't expect things to get better in the future. "When you look at the projected trends in warming, the science is telling us that we'll lose as much as 50 percent of coldwater habitats," said Mathews. "It's unimaginable what could possibly happen to the fly-fishing business."

The NWF report does the math: By 2030, the number of days that anglers will fish is projected to decline by more than one million days every year. By the end of the century, it's over six million days. That would translate to a roughly $6.4 billion loss for the fishing industry annually.

Mathews and other anglers in the Yellowstone region were lucky this year. "We've been blessed with a little more moisture," Mathews said, and his outfit has actually seen a bit of benefit from the climate-driven misfortune of others. "As a result of fires in Sun Valley and smoke in Jackson and closures in other parts of Montana, we saw a spike in our business as people tried to escape those parts."

Not that Mathews is thrilled about the situation. "This year, it benefited us. But certainly it's benefiting no one in the long run."

Follow Ben Jervey on Twitter and Google+.

Jim McNellis
Jim McNellis

Long before water temperature rises to the point that it can no longer support a cold water fishery the water will be gone as a result of the insatiable demand of downstream agribusiness watering crops in the most inefficient manner imaginable in an arid environment that should be left as it is.

Dave Smethurst
Dave Smethurst

Robin, I've been trying to listen to all sides.  What research are you using to argue there has been no warming?

Robert, same question for you.  Debunked years ago - waht research are you using? 

Robin Lavender
Robin Lavender

Since there has been no warming for the last 15 years, it seems to me that this article is based more on false assumptions and ideology more than any actual science. I expect better from National Geographic.

Robin Lavender
Robin Lavender

Since there has been no warming over the last 15 years, this story seems based on false assumptions and ideology more than any actual science. I expect better from National Geographic.

Flower Jasmin
Flower Jasmin

The global warmists, pardon me, now it is climate change not global warming, shoot themselves into the foot by connecting everything to something that does not even seem to take place. Today there was another article how the ice did not really melt this year in Arctic but still trying to keep up the mantra of warming.

May be there is an evening out of the earth' temperature in general which has been happening for a long time. The reason for earth abundance is the even temperatures.

Robert Kosta
Robert Kosta

Since the climate warming/change sky is falling attitude was debunked years ago, it is interesting to see what sources the same pitiful stories continue to emerge from.

I think 'Climate Scientists' and writers like Mr. Jervey would be better served by trying to get some credibility back instead of talking about such lame ideas speculative effects on a few fishermen. 

Saying that unknown 'scientists' are in agreement is just false and another pathetic attempt to bring back the long discredited junk science of the IPCC, et al.  "Hide the decline and pass the grant money" - right?

T.O. Smith
T.O. Smith

As a 20 year veteran fish and wildlife biologist and executive manager who has managed the fisheries in Montana I always find it interesting to read comments that discuss how anglers are the problem.  It is like saying the reason we don't have enough groceries at the store is because folks are eating too much in stead of addressing how much we grow or how much the store orders each week.  Fisheries are a renewable resource as long as they have the habitat available to support them.  Anglers could stop fishing all together, but if the habitat is disappearing the so are the fish with or without the anglers. I don't hold this lack of education or understanding against the folks who are nay-sayers, but I challenge them to think deeper about how much economy these angling activities bring to rural areas,  and also to what the real problem is.  It's not that we fish too much its that we have fewer and fewer fish each year that we can angle for.

Aaron Reed
Aaron Reed

Climate change is actually having at least one positive effect on the Texas coast; in recent years snook and mangrove snapper (not to mention mangroves) have expanded their ranges northward along the coast (they've been there before, but not recently) and milder winters have given us a pass on the high mortality freeze events (which affected all inshore game fish species here) we used to see every 6-9 years. There will be winners and losers in any climate shift; it's a win for the species I most value.

wilbur goldstein
wilbur goldstein

Amazing to hear the guides, outfitters, fly shops, and Trout Unlimited all crying about the "damage to the resource" from warming. For the past 20 years this cabal has been on a veritable crusade to destroy the resource - not protect it - each trying to out-plunder the other. Closing rivers in MT due to low flows is nothing new, and has nothing to do with climate change. The crocodile tears bespeak the effect it has on their collective wallets not their eco-sensibilities. What is new is this sanctimonious group of eco-capitalists putting attorneys and bankers from "the city" on overfished trout in the dead of summer, all so they can experience their own River Runs Through It moment. Instead of getting all preachy with National Geographic and their readers, they should put their boats away and clean up their mess.

Xira Arien
Xira Arien

As sad as this is, there isn't much we can do.

Global warming is 'baked in' for the next 100 years, and will continue even if we go back to mud huts and stop emitting carbon tomorrow.

We should have acted when we had the chance. <- my blog

John DeVoe
John DeVoe

Climate change exacerbates human caused loss of coldwater habitat. Agriculture - and in these Montana watersheds - primarily water diversions for pasture and feed for cows - is the largest out of stream use of water by far. This has huge impacts on streamflows, water temperature and water quality. This article fails to discuss that factor. 

Want to address some of the impacts of climate change on coldwater habitat? If so, agricultural use of water will need to better managed. In my home state of Oregon, more than half the diversions in the state lack any form of measurement and compliance with measurement conditions in water rights has plummeted to around 20%.  You can't manage if you don't measure. 

Also, water is free across the West. Without a price signal for the water itself, there is not sufficient incentive to conserve. 

We can do a much better job with our allocation and management of water to address the impacts of climate change, protect and restore coldwater habitat and continue farming.  But we'll have to make investments and change the way many in the farming world have operated for the past century plus.

Aldo Leupold
Aldo Leupold

In California, the warmer water is caused by big-agribusiness sucking up water to grow almonds and grapes in a desert, and the political shenanigans that allow the mis-management of said water. Very little water in this state (and I am sure many other states) is solely in mother nature's control, and it is suspicious to me that the author ignores that fact, when it is such a major contributor to the temperature of a stream?

I would question how much of these other streams are unmanaged for water removal by agriculture (easily the culprit of most stream/river warming,) and how many years these small percentage of unmanaged streams have been measured for temperatures changes. Being in a drought currently,, of course they are warming,, show me "normal" temps over a 20-30 year mean.

The more I read this article the more it sounds like it was written to justify the author's prejudice instead of written to objectively research an issue..

Albert Cadda
Albert Cadda

@c kaf You asked: "What does sea lamprey taste like"?

It tastes like chicken!


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