The Fish Question

Longread: The Dolores Canyon, native fish vs. trout, and climate change

Earlier this summer, when it became clear that the operators of McPhee Dam would cut releases to a trickle, essentially leaving the Lower Dolores River riverless, the outcome became clear: Most if not all of the trout in the river below the dam would perish. The flows would simply be too meagre, and the water temperature too high, to sustain a species more accustomed to cool, clear, fast-moving streams. The Dolores certainly is not the only imperiled fishery in the region. In the Northwest, salmon runs are in serious trouble thanks to the combination of climate change and dams. Montana trout are stressed out, as they are on a number of Western Colorado stream segments in addition to the Dolores.

After news broke recently about yet another Colorado fishery in trouble, someone on Twitter pointed out the fact that the fish in question—rainbow, brown, and brook trout—were not native to the region, had been introduced into Colorado’s streams in the late 1800s, and had been stocked by the thousands ever since. They were merely pointing out a fact, not saying that the fish kill offs weren’t tragic or alarming. But for me it resurfaced a long-lingering questions about nature, wilderness, and introduced species—or what I called, in River of Lost Souls, “The Fish Question.”

And the Fish Question—along with the sad news about the Dolores—brought up memories of going down into the Dolores River Canyon in the summers before and after the dam, and the changes I witnessed. So I give you, for your long-read pondering, a reminiscence and “The Fish Question.”

Back before McPhee Dam was built on the Dolores River, when I was still young and when the valley that would be inundated was still teeming with archaeologists trying to salvage what knowledge they could, my family and I went on occasional camping excursions in the Dolores River Canyon. 

To get there we had to drive almost to Dove Creek, where we turned onto a network of county roads that took us across countless beanfields—back then it really was the Pinto Bean Capital of the World, complete with a Pinto Bean Queen—before finally dropping down to the Dove Creek pumphouse. 

The drive always seemed interminable to me, perhaps because my brother and I had to ride the whole way in the back of my grandparents’ old International Harvester pickup truck with the camping gear, huddled up against the cab for a smidgeon of protection from sun and wind, sloshing back and forth at every highway curve, and bouncing around on the hot metal as we bumped along the bone-chattering road in the canyon bottom.

Once or twice we went down into the canyon in late May or early June, the height of spring runoff, so that my father could photograph rafters as Snaggletooth, the gnarliest rapid on the river, pummeled them. It was long ago, but I can still remember the befuddlement on the rafters’ faces when they saw this family parked alongside the river in an old, beat up farm truck that burned through a quart of oil an hour. They had been convinced that the only way to get to a place so wild was by boat. They seemed miffed that we had wrecked their illusion. That is, until my parents used the truck to help them pull an inextricably wrapped raft off of the Snaggletooth. 

That was probably the late seventies, maybe early eighties, and the dam was well on its way. One of those groups of rafters was some kind of special trip held either to build support for stopping the dam, or maybe to mourn its construction and get one last chance on the roiling, raging waters before they were tamed. I’m pretty sure Phil Hyde, the landscape photographer, was on the trip, along with Ed Abbey. I have an old slide of my father’s, showing Abbey—or at least someone who looks like him—as a passenger on a vintage raft, wearing jeans and a vest under his life vest as he drops into the white waters of Snaggletooth.

Observing spring runoff and rafting carnage was pretty cool, but I still preferred the late summer outings, when big spring waters had been reduced to a mere trickle, thanks in part to the normal hydrological cycle, but mostly because nearly all of the water was being pulled out of the river below Dolores and carried via canal and ditch to the irrigators in the Montezuma Valley around Cortez. By late July or early August, all that remained of Snaggletooth was a skeleton: massive boulders perched along a dry riverbed. Downstream, the rushing water had eaten down into the bedrock to leave gaping holes in which the water pooled, cool and so deep I couldn’t see the bottom, no matter how hard I peered into the glassy murk. 

We camped alongside these pools, sometimes at the red wall not far below Snaggletooth, sometimes on the sandy beach down past the big bend, which required a precarious ride along a rough, narrow road high above the river. Aside from the red rock canyon walls towering above us, the sandy camp seemed somehow out of place to me. I guess it must have been the beach, or the bottomless, still pool, or the thickly vegetated riverbank, shaded by the foliage of boxelder trees and willows.

My parents lounged around, cooking or drinking beer or smoking cigarettes or reading, while my brother fished and I chased crawdads or floated around on a little innertube, trying not to think of the giant catfish lurking below. Yes, catfish. Trout couldn’t make it in those waters; it was just too warm. As for the warm water-loving native fish—pikeminnow, roundtail chub, bluehead sucker—I suspect they couldn’t compete with the catfish and weren’t too keen on the lack of current, besides. 

When the dam was completed in 1985 it changed everything—and nothing. The plan was to withhold the raging waters of spring in order to give more irrigators more water for longer in the season, while also releasing enough cold water into the river to sustain a trout population below the dam. During the first several years the plan worked pretty well, mostly because those 1980s winters were epic, dumping snow so deep in the mountains that Lake Powell—the big barometer of the hydrologic health of a good swath of the Interior West—was chock full and then some for a decade. Irrigators got plenty of water to grow alfalfa and corn and wheat, and there was still enough leftover for the river. 

I went down into the Canyon in the late spring of 1989 with a high school class. It did seem different. The vegetation on the riverbanks was greener and the riparian ecosystem visibly healthier, thanks to a year-round flow in the stream. We saw river otters that had been reintroduced and were thriving. And there were trout, too, at least for a dozen or so miles below the dam, able to survive now that there was a constant current of chilly water. Around the same time, my father and brother and I went further down-canyon, where the water had warmed slightly, to fish, and my brother caught a native chub, I believe; he gingerly unhooked it and tossed it back in the water since by then it was officially an imperiled species. The catfish were all gone so far as we could tell.

It seemed, at the time, that nature had begun healing from the wounds that a century of irrigation withdrawals—as well as uranium mining and, further upstream, hardrock mining—had inflicted. And that the dam was partially responsible for the rescue.

Now, especially after observing and researching and pondering the situation in mining-affected Animas River, I’m not so sure it was a matter of healing so much as it was humans recreating something that never really existed in the first place. Sure, there were native trout in the Dolores River back before the white folks showed up, but it seems unlikely that they would have made it down to the lower reaches, given how warm the water was, even without massive irrigation withdrawals. It’s far more plausible that the river below where the dam now sits was populated by native pikeminnows and chubs and suckers. And now, thanks to efforts to build a trout fishery there, the water (when it exists) is too cold for them.

Perhaps these questions are moot now that climate change and water consumption have combined to dewater the river almost entirely, probably killing all fish—native or otherwise, warm- or cold-water—in the process. But as policies and priorities change, and some water is returned, hopefully, to the river, we’ll need to start asking the Fish Question once again in order to determine just what means to heal Nature.



The high mountain streams were running ice-cold and clear in July 1985 as Bill Simon shouldered an awkwardly-weighted backpack just northeast of Silverton. He wasn’t toting gear for some alpine excursion. In his pack he carried thousands of fingerling trout, to be released into Minnie Creek, a small tributary of the Animas. The fish were a question. The answer would change everything. 

Bill Simon grew up on Colorado’s Front Range in the 1940s and ’50s, where his dad, a machinist, tried his hand at farming. When that didn’t work out, a young Bill took over, leased the farm, and turned a profit. He attended the University of California, Berkeley, on a ski scholarship in the 1960s. After earning his undergraduate degree, he went to work on getting his doctorate in evolutionary ecology on a NASA fellowship. He helped start the Environmental Studies College there, and was on the founding board of Earth Day. 

The Vietnam War was raging, and the military started taking an interest in Simon and the work he was doing. That’s when the young scientist, who had also been doing some community organizing with the anti-war effort, decided it was time to go. He took a “permanent leave of absence” from Berkeley and landed in Silverton, as do so many other refugees from the outside. Simon found work on salvage mining operations, going into closed and abandoned mines and recovering ore that had been left behind. Later, he did some large-scale welding, building cyanide mills for the Sunnyside and Pride of the West mines. He even worked a bit at the Gold King for Apache Energy, which had designs, never realized, on reopening the long-defunct mine. Oftentimes, after completing whatever work he was hired to do, Simon would also clean up some of the junk from the old mines, and even plant a few trees. 

The Colorado Department of Public Health and Environment and the state Division of Wildlife (now Colorado Parks and Wildlife) had pronounced most of the Silverton Caldera’s waters “dead,” thanks to natural mineralization, acid mine drainage, and tailings spills. As Simon cruised around the backcountry for work and for fun, he began to doubt the state’s assessment. Sure, Cement Creek was never going to support fish, and probably never has. But other stream segments appeared healthy, even if they were fishless at the time. Maybe they could support trout. 

In 1984 Simon was elected to the San Juan County Board of County Commissioners. It provided him a platform from which he could test his theory using fish as his guinea pigs and the watershed’s streams, beaver ponds, and lakes as his laboratory. With a group of miners, who were also anglers, he hiked into the backcountry carrying packs that held thousands of tiny brook and cutthroat trout, donated by the state Division of Wildlife, and poured them into the healthiest-looking streams and lakes. 

Over the months to come, Simon and his fellow citizen stockers returned to their test streams and checked on the experiment’s progress. To their surprise, the fish in some places were doing well, and a smattering of the brook trout, a hardy, though non-native species, grew to as much as two pounds. The Clean Water Act’s listed objective is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” Its goal was to eliminate the discharge of pollutants into navigable waters by 1985, and “wherever attainable, an interim goal of water quality which provides for the protection and propagation of fish, shellfish, and wildlife … be achieved …” Prior to Simon’s experiment, the “wherever attainable” phrase did not pertain to the Upper Animas. Now it did. 

Most of America’s environmental initiatives were built upon the notion that these lands, waters and the air were pristine, wild, and void of human influence prior to the arrival of Euro-American invaders. This was a place of “chemical, physical, and biological integrity,” a place, as the Wilderness Act puts it while erasing thousands of years of Indigenous history, “untrammeled by man, where man himself is a visitor who does not remain.” All was in harmony, until the colonizers, the miners, the loggers, and the hunters came and subdued the earth, poisoned the waters, and killed the fish. The job of the Clean Water Act, the Clean Air Act, and the Endangered Species Act, then, is to restore the Paradise that was lost.

Eden, however, was a lot messier than once imagined. Pristine is an illusion. Humans altered the landscape for millennia before the Euro-American invasion. Archaic hunters may have wiped out ancient megafauna. The Ancestral Pueblo people likely cut down trees, hunted game, planted the soil year after year—perhaps depleting the resources at their disposal. Evidence suggests that the Ute people torched forests to drive deer and elk into their arrows, and burned grasslands to increase forage for game. And long before that, without the help of humans, some streams issuing from the Silverton Caldera ran orange with iron and others milky-green with aluminum. 

Simon’s fish experiment showed that fish could live in some parts of the Caldera. Yet it left another unanswered: Did fish ply these icy waters prior to mining, and if so, which species? Only by answering it will we know whether the efforts to clean up the watershed amount to restoring something that was lost, or creating something new, an artificial world fashioned after the settler-colonial myth.

 There is no baseline data in this regard. The journals of the early Spanish explorers offer clues to what the ecology along the paths they followed looked like, and some of their botanical descriptions are illuminating. Yet they rarely mention aquatic flora and fauna except when Silvestre Vélez de Escalante writes about the Timpanogos people near Utah Lake, whom he calls “fish-eaters.” Archaeology is not helpful: fish bones haven’t been found in any abundance in Animas River Valley ancestral Puebloan sites.

The first white settlers give a few more clues. In 1872, George Howard, one of the early white settlers of Bakers Park, hiked from what would become Silverton, up Mineral Creek, over what is now Ophir Pass, to the San Miguel River drainage and Trout Lake (née Fish Lake née San Miguel Lake) with two friends. From log rafts, using bacon and grasshoppers as bait, they caught a total of 220 fish, which they packed back into Baker’s Park and sold to other miners for $1.50 per dozen. This suggests that the lakes closer to Silverton, in the upper Animas watershed, were devoid of fish, or at least were less bountiful than the trout-rich lake to the west.

The 1874 Hayden expedition, which included among its ranks that chronicler of a disappearing Eden, Franklin Rhoda, spent a few words on the ichthyology of the region. “No fishes were collected, although numerous attempts were made,” wrote Ernest Ingersoll, the trip’s zoologist. “The majority of our time was spent where they seemed to be entirely absent, or so extremely scarce that, although all were interested in the capture of certain species, not a trout graced our table during the whole trip.” Yet they, too, traveled to Trout Lake on a peak-bagging expedition, and noticed that it was teeming with trout. Apparently they made no attempt to catch the fish. 

Ingersoll and Hayden didn’t make any systematic study of fish; their faunal focus was on mollusks—mostly freshwater or terrestrial snails. Cunningham Gulch, a cold, clear brook that enters the Animas River a few miles upstream from Silverton, was particularly rich with various freshwater and terrestrial snail species, including Pupilla blandi, Vertigo californica, and Zonites fulvus, which Ingersoll found slithering along a snowbank at 11,000 feet in elevation. 

Rhoda described Mineral Creek at its junction with the Animas River just below the new town of Silverton as being “highly impregnated with iron, sulphur, and other ingredients. … Almost all the water in this country is as pure as any in Colorado, but this stream is so strongly impregnated with mineral ingredients as to be quite unfit for drinking.” Oddly, neither Rhoda nor anyone else in his party similarly described Cement Creek, which today is considered the nastier of the two streams. But geologists, looking at ancient iron deposits on Cement Creek’s banks, have concluded that the water was always filled with iron to the extent that it never could have supported fish, even before mining.

It was not until Rhoda got down to “Animas City,” the abandoned settlement that the Baker party had founded near what is now Baker’s Bridge, that he mentioned fish in the Animas. “Trout are found in the river here, but how abundantly I cannot say,” he wrote. “They have never been caught as far up as Baker’s Park (Silverton)—due, probably, to the falls between the two points.” Rhoda was referring to the Rockwood Gorge, a narrow stretch of granite-walled canyon above Baker’s Bridge through which the Animas River rushes. There are no waterfalls, per se, but the gorge is choked with boulders and rapids that challenge even the most intrepid kayakers, finishing off with a “sieve” of rocks and debris that will kill anyone who attempts to boat it.  

Rhoda may have been right about a dearth of fish around Silverton, but his explanation was likely wrong. Trout are able swimmers, and while they can’t make it up high waterfalls, they should have been able to navigate the Rockwood rapids. Nevertheless, the theory would hold for a time. In March 1885, Colonel Francis Snowden set about to fill the upper Animas fish void. He got forty thousand hardy, non-native, red-speckled eastern brook trout from a hatchery in Denver, and dumped them into the Animas River above Silverton. “Heretofore no trout have ever been known in the Animas above the falls in the box cañon just above the town of Rockwood,” wrote the editor of the Dolores News, sticking with the Rockwood theory. “Below that point, fine trout have always abounded and all that was needed in the upper Animas was a start.”

Finally, four years later, ichthyologist David Starr Jordan made an exhaustive survey of the fish in nearly every river basin in Utah and Colorado. It’s a fascinating account, in which he catalogs the diverse and sometimes odd array of fishes in the Colorado River Basin and its tributaries and also lays out some of the existential threats to the same fish. 

Of the Animas River, Jordan wrote: “Above its cañon of ‘Lost Souls’ it is clear, shallow, and swift flowing through an open canon with a bottom of rocks. In its upper course it is said to be without fish, one of its principal tributaries, Mineral Creek, rising in Red Mountain and Uncompahgre Pass, being highly charged with salts of iron. In the deep and narrow ‘Cañon de las Animas Perdidas’ [presumably the canyon between Silverton and the Rockwood Gorge] are many very deep pools, said to be full of trout.”

Since Jordan did not survey the canyon himself, he doesn’t know what species lurked in the deep, jade-green pools. Therefore he couldn’t say whether they were native Colorado River cutthroats that had been there all along, regardless of the “falls” at Rockwood, or brook trout that had been stocked upstream then got washed into the canyon. And that leaves the pre-mining fish picture of the Upper Animas River rather fuzzy.  

The snapshot of the Animas River below Rockwood is far sharper. Jordan and his colleagues did run nets through portions of the lower Animas River in the Animas Valley, which he refers to as Hermosa Park, and above and below Durango. Along with plenty of trout, presumably native and non-native, he also found a cornucopia of indigenous fish suggesting that Eden was a bizarre place indeed. Among the finned characters he encountered were Catastomus latipinnis, Pantosteus delphinus, and Agosia yarrowi, two suckers and a minnow. They found Cottus bairdi punctulatus—mottled sculpin, miller’s thumb, the blob—under nearly every rock. As kids, my brother and I used to catch these homely, bigheaded, prehistoric-looking things in the Animas River in Durango with our hands for no particular reason except because we could. 

Xyrauchen cypho,or razorback suckers, skulked in the murky green waters. With their torpedo-like heads giving way to a prominent humped back, they look like a fishy eighteen-wheeler with an especially tall trailer. And then there were Ptychocheilus lucius, “which ascend the river in the spring, going back to deep water after spawning in the summer.” This monster was commonly known as “white salmon.” Nowadays it goes by Colorado pikeminnow. These things can live for up to fifty years and grow to be six feet long; the biggest pikeminnow ever caught weighed ninety pounds. Old newspapers tell of anglers regularly reeling in twenty and thirty pounders on the Gunnison River near Delta and the Colorado River near Grand Junction. Colorado law allowed anglers only five pounds of trout per day, but set no limit on carp, suckers, and white salmon. The best bait was a whole mouse.

Pikeminnow travel extreme distances at times. In 2014, tagged fish were caught in Lake Powell, 144 miles downstream from where they were stocked. Once, these giant, finned torpedoes migrated throughout all but the coldest waters of the Colorado River Basin. But Glen Canyon and other dams all but extirpated them in the lower Colorado River Basin, and only several thousand still survive in warmer, upper reaches of the basin. There are probably fewer than fifty wild pikeminnows swimming the silty waters of the San Juan and its tributaries these days. But they are no longer the titans that they once were, and rarely grow larger than three feet long.

Large-scale milling of ore was just getting going in the San Juans when Jordan came through, so he didn’t witness the river in its gray and turbid, mill-slimed state. He did note that in the Platte River and Arkansas River basins of eastern Colorado, “placer-mining and stamp-mills have filled the waters of otherwise clear streams with yellow or red clay, rendering them almost uninhabitable for trout.” But in the southern and western part of the state he saw an even bigger danger—irrigation. He wrote: “Below the mouth of the cañons dam after dam and ditch after ditch turn off the water. In summer the beds of even large rivers (as the Rio Grande) are left wholly dry … the beds of many considerable streams (Rio la Jara, Rio Alamosa) are filled with dry clay and dust. Great numbers of trout, in many cases thousands of them, pass into these irrigation ditches and are left to perish in the fields. The destruction of trout by this agency is far greater than that due to all others combined, and it is going on in almost every irrigation ditch in Colorado.” 

The ichthyologist, however, was not similarly concerned about what effect filling up the streams with non-native fish would have on the aquatic biodiversity. He was a big advocate of stocking, and urged wildlife commissioners to keep adding rainbow and brook trout to Colorado’s coldwater streams and catfish to the slower, muddier, warmer rivers, like the San Juan and the Colorado. 

Within a decade of Jordan’s study, the streams of the Animas River watershed had been completely altered, not just by the mill tailings and acid mine drainage now sullying the waters, but also by an industrial-sized program of fish stocking. The Colorado fish and wildlife agency dumped not only thousands of brookies and rainbows into the Animas River, but also, in the late 1890s, largemouth black bass, of all things. Carp escaped from private ponds and colonized the river. In 1898, ten thousand trout were dumped into Molas Lake above Silverton, an event hailed as “the first batch of any fish dumped into the lake by the hand of man.” A decade later, twenty-two thousand trout fry were dumped in South Mineral Creek, the “clean” tributary to the larger Mineral Creek. By the 1920s, the state fish and wildlife agency was stocking nearly every creek in the watershed; soon they’d be dumping fry into high alpine lakes with helicopters. As of today, some seventy non-native fish species have been introduced into the Colorado River Basin, and at least twenty of these still swim alongside the few remaining native suckers, chubs, and pikeminnows in the San Juan River and its tributaries, including the Animas River. 

By the time Simon came around with his fish experiment, we could no longer distinguish between the natural world and the world we had imposed on Nature. We didn’t know if our Eden ever had fish, or if our mines had come along and killed them. As for all these efforts to make amends, it is not at all clear whether we are clawing our way back to Paradise Lost, or are merely restoring something that never really was, rebuilding our own constructed facsimile of Eden. 

Excerpted from River of Lost Souls: The Science, Politics, and Greed Behind the Gold King Mine Disaster, by Jonathan P. Thompson, Torrey House Press, 2018.

And, finally, a little bit of real healing of theDolores River, courtesy of a strong monsoon (with help from humans):