Like so many transplants, Hutch Hutchinson fell hard for Colorado. It was autumn 1986, and the New Hampshire native had just wrapped up his second summer as a fly-fishing guide in Alaska when he made the cross-country drive from New England to Aspen. His brother had recently moved there, and the then 24-year-old Hutchinson was simply planning to visit for a few days. Instead, he called his mom and asked her to ship his stuff west.

A lot has changed since then. Hutchinson started a family, made the transition from guiding to being a travel specialist for Vermont-based fishing giant Orvis, and in 2015 co-founded the Roaring Fork Fishing Guide Alliance, a professional organization dedicated to the conservation of the region’s fisheries. The Roaring Fork Valley has changed, too. Pitkin County’s population has grown by more than 60 percent since 1986, development has increased dramatically, and right around the time the alliance got off the ground, Hutchinson began to notice ominous shifts in his home rivers.

Two of the most noticeable were that water levels were dropping lower and lower and temperatures were climbing higher and higher during the peak summer season. Both conditions can prove deadly to trout, but well before that happens, good sportsmanship demands anglers hang up their rods: While trout can survive water temperatures in the high 70s, at least for a few days, they often can’t endure being hooked and released when those temperatures creep above 67 degrees. “As water gets warmer, it holds less dissolved oxygen,” says Tom Rosenbauer, a fly-fishing educator and Orvis’ chief enthusiast (which is, apparently, a real job title). “So when you go and jerk trout around on the end of a line, you are stressing them further. They can literally suffocate.”

By this past fall, Hutchinson had seen enough. At an alliance board meeting in September, he told his fellow members that fishing outfitters in the valley and around the state needed to start thinking seriously about how to adapt their businesses to accommodate climate change. “These discussions need to happen now,” he says, even if it’s “probably already too late.”

Last summer saw record high temperatures across Colorado, exacerbating a historic drought on the Western Slope. Parts of the Dolores River, a popular fishery northwest of Durango, all but dried up, and Colorado Parks and Wildlife (CPW) implemented at least 16 voluntary closures (during which the agency asks everyone from tubers to anglers to stay off the water but doesn’t forbid it) and one mandatory closure on sections of eight rivers to protect stressed fish. But as bad as summer 2021 was, the future looks worse.

Fly fishing in Altmont Colorado. Getty Images

Over the past decade, a team led by Dan Isaak, an Idaho-based biologist with the U.S. Forest Service’s Rocky Mountain Research Station in Fort Collins, has been compiling temperature records from various rivers and streams across the Western United States into a comprehensive database. In 2014, Isaak and other researchers began using that data to predict temperature shifts in the region’s waterways; four years later, they found that by 2050 there will be an average increase of 1.8 degrees Fahrenheit. Furthermore, Isaak’s research shows that unless the world gets serious about tackling the climate crisis, the increase will jump to nearly 5.5 degrees by the end of the century.

That’s not enough to make trout disappear, but it could have major effects on where they’re able to live, much less thrive. “As the water gets warmer, they’re going to have to move up in elevation [where it’s cooler] to maintain their equilibrium with the environment,” Isaak says. According to his research, that could result in an eight to 31 percent decrease in suitable habitat in the West as some rivers and streams are pushed past trouts’ thermal tipping point.

But climate change is about much more than just rising temperatures, says Diana Lane, director of the Sustainable Food and Water Program at the Nature Conservancy’s Colorado field office. “When you think about warming, people immediately go to high summer temperatures,” she says, “but there is a whole complicated cascade.” If the snow melts earlier in the year, for example, there will be less running water during the summer, and rivers with low flow not only heat up faster, but they also have fewer deep pools in which cold-water fish can seek shelter. If a trout does find a pocket of cool water, it can become trapped if its refuge is surrounded by low or warm water, making it easy pickings for predators. Plus, earlier snowmelts and longer, warmer summers also have the potential to affect the life cycles of the insects trout depend on for food and possibly the trouts’ breeding schedules.

The swimmers that do escape to higher elevations aren’t out of danger, either. As their habitat shrinks, some trout populations could become isolated, increasing the chance that climate-change-driven natural disasters—such as fires, mudslides, and extreme flooding—could wipe them out, Isaak says. In 2018, CPW staff had to hike into the path of the 416 fire near Durango to rescue an endangered strain of cutthroat.

Add angling to the mix, and things get even more complicated. While there will still be plenty of water cool enough for trout to survive, there will be fewer places and fewer days where water temperatures are in a safe range for fishing. Isaak’s water temperature database has records for a handful of popular Colorado cold-water fisheries. After identifying monitoring sites with multiple years of data, 5280 averaged the daily high water temperatures from June through September to see how often those locations reached the critical 67-degree cutoff for safe trout fishing. Only a few did regularly, but when we added the predicted temperature increases, the number of warm-water days exploded.

Blue River. Nathan Bilow/Getty Images

A monitoring site just downstream of Evergreen on Bear Creek, for example, only reached 67 degrees or above an average of nine days a year between 2009 and 2015 (data is missing for part of 2012 and all of 2013). In 2050, however, that number could jump to 50 days a year, and in 2100 it would be a whopping 83 days. The Roaring Fork River near Glenwood Springs, Hutchinson’s home turf, could average 17 warm-water days in 2050 and 62 warm-water days in 2100. That means that by the turn of the century, those two stretches of river could be off-limits to anglers and guides alike for at least part of the day for the entire summer. That will have huge implications for fly-fishing outfitters. Hutchinson estimates that June, July, and August account for around 65 percent of fly guides’ annual business. Says Hutchinson: “That’s their bread and butter.”

“We don’t like to tell people what to do,” Rosenbauer says, speaking of Orvis’ recent efforts to nudge customers away from fishing for trout in the summer and toward warm-water species like bass—or, failing that, to at least persuade them to seek out high-elevation streams and lakes where the trout are under less stress. “We try to educate them that, Hey, this warm-water stuff can be just as fun as trout fishing.”

The fact that the world’s most iconic fly-fishing brand, which built its image around trout for much of its 166-year history, is attempting such a shift highlights how climate change is poised to disrupt the business that surrounds the sport. And it’s big business: A 2018 analysis done for CPW found that fishing contributes $2.4 billion in economic output each year in Colorado and supports some 17,000 jobs in the state. No one is sure how climate change will affect those figures­­­—only that it will. We have to plan for the possibility that the latter part of July and a good chunk of August won’t be good fishing on rivers like the Roaring Fork and the Colorado in the future, Hutchinson says.

That’s already happening on a small scale. The owner of Silverthorne outfitter Cutthroat Anglers told the Denver Post this past August that he had to cancel 16 guided trips to comply with a voluntary CPW closure. On the Yampa River, the site of last summer’s only mandatory closure, Johnny Spillane, owner of Steamboat Fly Fisher, says shutdowns have hurt his shop’s retail sales but haven’t affected guided outings. “We’re really clear when we are booking trips that if the water reaches a certain temperature, we are shutting it off,” he says. “We combat that by just fishing half days and getting off of the water before it heats up.” There are also places nearby at higher elevations to take clients, he says.

Having to travel higher and farther to find ethical fishing is the most common prediction for what the future holds, but Hutchinson believes outfitters and guides also need to start booking trips into November as climate change shifts ideal conditions to later in the year. “It’s going to be a learning process,” he says, both for the industry and for its clients.

Others have grimmer outlooks. “I am sure we will see more restrictions on the times you can fish, where you can fish, and on the number of anglers,” Isaak says. “It could almost get into a situation where it comes down to a [lottery] system, like on the most popular whitewater rafting rivers, to regulate the quality of the experience.”

Isaak has another prediction, as well: Tailwaters, the sections of rivers directly downstream of dams, will become evermore coveted and crowded fishing spots. If a reservoir is deep enough, the cold water released by its dam can mitigate the effects of climate change for dozens of miles downstream. Nonprofit organizations such as the Nature Conservancy already help fund strategic water releases, and CPW has agreements with partner agencies and municipalities that have water rights to do that, too. Because those agreements are voluntary, however, rights holders will not be legally obligated to continue them as water becomes scarcer in the future.

“CPW is trying really hard to work with those entities,” says Josh Nehring, an assistant aquatic section manager at the department. “There are certainly areas in Colorado where agencies or people that hold water rights can completely dry up a stream.” That’s part of what happened on the Dolores this past summer: The river irrigates thousands of acres, and after two decades of drought, there wasn’t enough water for both fish and farmers.

Coloradans are working to protect their favorite fish—so that they can hook them—in other ways. Nonprofits such as the Yampa Valley Sustainability Council are planting shade trees along important waterways; the Colorado Water Conservation Board has water rights or agreements on parts of 45 rivers and streams to ensure they don’t run dry; and CPW’s Wetland Wildlife Conservation Program has funded the restoration or protection of riparian zones along hundreds of miles of public and private riverbank since 1997. But with over 58,000 river miles in the state, some 12,000 miles of which are home to trout, closures will remain one of the main tools for protecting the state’s cold-water fisheries. Hutchinson believes voluntary closures are smart, and the Guide Alliance even works with CPW to get the word out when they’re announced. But he thinks there have been times when people have been confused by the agency’s decisions, and some anglers say the agency isn’t being proactive enough to keep up with changing water conditions.

It’s not just nonprofits and the government that need to step up; the public has to take the initiative, too, Rosenbauer says. On popular rivers, a single trout can theoretically be caught five or six times a week, he says, and the stress each fight causes can last a couple of days. So, in the future, anglers may have to limit how many trout they catch and release each day, not just how many they keep. “Be happy with three fish on a hot day,” he says. “It’s either going to be that or someone is going to have to start regulating fishing pressure, and no one wants that.”

By at least one metric, Colorado anglers seem up to the challenge. Although fishing closures have slowed the retail side of Spillane’s Steamboat Fly Fisher, one item has seen its sales increase: thermometers. For the past few years, customers have been buying them at around quadruple the rate they had previously to test water temperatures. This means many Coloradans are considering the life of a trout before they even get to hold one in their hands.

(Read more: How Denver Anglers Got Hooked on Carp)

This article was originally published in 5280 May 2022.

Nicholas Hunt
Nicholas Hunt

Nicholas writes and edits the Compass, Adventure, and Culture sections of 5280 and writes for 5280.com.