It has been more than 50 years since aquatic biologists introduced a solution for anglers seeking the spirited fish that typically spend their lives at sea.
Spawning kokanee by © Scott Willoughby

In a state that pretty much has it all, the most glaring gap in Colorado’s vast menu of outdoor options becomes obvious at its borders. The ability to walk across state lines almost anywhere without getting your feet wet serves as evidence of a basic reality: We’re landlocked. High and dry.

For a large chunk of the fishing world, that could be considered a problem. There are plenty of fish in the sea, as they say, and the opportunity to chase a wide variety of them is what drives many an angler to wet a line. But in the network of rivers and lakes draining from the mountainous spine of the nation to oceans east and west, well, the species selection falls a bit short by comparison. Sure, we’ve got a respectable assortment of more than 40 types of cold-, cool- and warm-water fish species statewide in Colorado, but it seems like the grass can always get a little greener.

And so it has.

The optimists among us tend to look beyond problems by focusing on solutions. And who can be considered more optimistic than a fisherman? After all, standing alongside a lake or stream with a hook and a string in the hopes of attracting a fish to bite is nothing short of an act of faith. Doing it in the hopes of catching a salmon — more than a mile above sea level and a solid 1,000 miles from the Pacific Ocean, no less — now that demands some bona fide conviction.

Or better yet, some kokanee.

It has been more than 50 years since resident aquatic biologists introduced the solution for Colorado anglers seeking the spirited sport fish that typically spend the majority of their lives at sea. Sockeye salmon (Oncorhynchus nerka) are an anadromous species of salmon found in the northern Pacific Ocean and many of the rivers flowing into it. A smaller, but no less feisty, variation of the sockeye — the ones we call kokanee — live their entire lives in freshwater and have thrived in the lakes and rivers of Colorado since fish stocking began in Blue Mesa Reservoir on the upper Gunnison River in 1965.

Since then, those fish known for going against the flow have established populations in more than 25 locations across the state, offering anglers interested in an extraordinary fishing experience an alternative to the typical trout. And while there are closer places to find salmon fishing from the population centers along Colorado’s Front Range — including Lake Granby, Williams Fork Reservoir, Spinney Mountain Reservoir, Wolford Mountain Reservoir and Green Mountain Reservoir (and the surrounding rivers) — the epicenter of the kokanee community, hands down, remains the upper Gunnison River valley.

Spencer Hemker fishes the Gunnison River. Photo by © Scott Willoughby.

“I feel like this is as close to ocean fishing as you can get in Colorado,” Montrose native Alex Hotze said during his traditional fall migration to the Gunnison River surrounding Blue Mesa Reservoir. Hotze’s dad, Hank, was one of the original outdoor outfitters in the region, founding Gunnison River Expeditions in the 1980s and teaching his son a few things about Colorado salmon fishing along the way.

Among the most fundamental principles is understanding the kokanee’s innate mapping imprint that drives the fish upstream toward their birthplace every autumn after they reach the appropriate spawning age. Typically around their third summer’s end, the fish leave the deep water of the reservoirs they’ve grown up in and stick their snouts into the current to fight their way back to their place of origin. Charged with reproductive hormones, kokanee females develop a red- and gray-white pattern while the males develop a hook jaw called a “kype” and turn a brick red reminiscent of the fall foliage as they head toward their place of origin in an attempt to spawn the next generation.

Success is dependent upon a lengthy string of variables, including your interpretation of “success,” which typically includes wildlife managers capturing the fish and milking the eggs as the fish try to reach the hatchery where they were reared. For Blue Mesa kokanee, that rearing unit is the Roaring Judy Hatchery along the banks of the East River just above its confluence with the Taylor River (where it takes the name Gunnison) near the tiny town of Almont.

Since kokanee are not a native species in Colorado, their management is somewhat complicated. Blue Mesa Reservoir serves as home to fish responsible for about 60 percent of the eggs needed for stocking kokanee at 26 lakes and reservoirs around the state. Before those eggs can be gathered, however, the fish have to run the 20-mile gauntlet upstream along the Gunnison, a moveable feast that must dodge eagles, anglers and a host of other perils along the way to the Roaring Judy Hatchery. Salmon that wash over the reservoir spillway will pool at the base of dams, unable to move any farther upstream.

Fishermen are forbidden from removing fish from the river between August 1 and October 31, but the opportunity for catch-and-release kokanee fishing remains, and should not be overlooked. (Since almost all kokanee reproduction occurs in the hatchery, fishing for spawning salmon in the river is considered fair game.)

Come fall, there may be no better way to reenergize a Colorado fisherman than by sinking a hook into the calcified jawbone of a hormonally crazed kokanee salmon putting up the final fight of its life (like their seagoing cousins, the fish are semelparous, dying after they spawn). Along the Gunnison, the action is enough to keep anglers entertained for miles.

“You know when you hook one, that’s for sure,” said Spencer Hemker, a Gunnison River fishing guide who studied wildlife biology at nearby Western State University. “Catching them early in the spawning run is especially fun. They’re still fresh, and if they’re in the river at that point, they’ve probably never been hooked. So they fight really hard.”

Life is no less challenging for the kokanee living in Blue Mesa Reservoir, where they are largely responsible for growing and sustaining a trophy lake trout population. Predatory lake trout also introduced to the impoundment as sport fish are dependent on a healthy kokanee population for nourishment, and their insatiable appetite has had a significant impact on the freshwater salmon through the years.

Kokanee fight really hard on the way to your net. Photo by © Scott Willoughby.

At one point in the early 2000s, more than 1 million kokanee lived in the reservoir, dipping to a low of less than 200,000 fish due to predation by lake trout before climbing to a population of about 400,000 in 2015. The decline in adult kokanee led to a subsequent decline in the number of eggs taken during the annual spawning run. In 2015, Colorado Parks and Wildlife (CPW) biologists harvested just 2.1 million eggs, well below the average of more than 6 million. About 4 million eggs must be collected to produce the 3.5 million kokanee fry required to stock Blue Mesa every year.

Low egg harvest creates an even larger problem because Blue Mesa has historically produced the most significant number of eggs to supply kokanee for other reservoirs throughout Colorado. Fortunately, other waters produced enough eggs to make up the difference for stocking last year.

With kokanee production and fishing contributing an estimated $29 million annually to the Colorado economy, developing the salmon fishery at Blue Mesa remains a priority for wildlife officials. During their life cycle, the fast-growing fish are the key species for maintaining a variety of angling opportunities in the reservoir and the nutrients that post-spawn salmon provide the Gunnison River help preserve it as one of the state’s premier fisheries.

“The kokanees are just a phenomenal energy source for the river,” Hemker said. “They’re kicking out eggs that other fish are eating. And after they spawn, they die, so they add nutrients to the water. I think it helps our fish get as big as they are.”

In order to keep the cycle going, though, it’s necessary to maintain the balance of the predator/prey relationship in Blue Mesa Reservoir so that each species can thrive. As lake trout numbers at Blue Mesa have climbed in recent years, kokanee numbers have dropped, prompting Colorado Parks and Wildlife aquatic biologists to increase stocking of kokanee and remove lake trout measuring 32 inches and smaller in an effort to reduce predation. In addition to the 3.5 million kokanee CPW stocks each year, the agency removes about 1,300 lake trout.

Biologists also believe that higher water levels in the reservoir during the past few years will help the kokanee. With more water in the reservoir, this open-water species gains more habitat, distributes more widely, and should be less vulnerable to predation.

Such news bodes well for the 80 percent of fishermen who visit the state’s largest reservoir in pursuit of keeper kokanee (the recently restructured regulations allow for a daily bag limit of five fish in still water, possession limit of 10), rainbow and brown trout. Even the minority of lake trout fishermen benefit from the abundant food supply the kokanee provide.

Bag and possession limits remain liberal for lake trout, although one recent change aims to allow more “trophy sized” fish to grow in the lake. Anglers can now keep only one fish per day that is bigger than 32 inches, down from 38 inches. Other than that, anglers are encouraged to keep all the lake trout they catch. CPW biologists explain that smaller lake trout, because of their numbers, consume the most kokanee. The average size of the lake trout caught by anglers is 19 inches. A big kokanee generally measures about 18 inches, although state record-holder Lee Cox managed to snag a 7-pound, 5-ounce kokanee measuring 27 inches at Blue Mesa in 2002.

With kokanee, however, it’s less about the size of the fish in the fight than the size of the fight in the fish, particularly in the fall. Driven by the single-minded mission to perpetuate the species, the freshwater salmon are prone to peeling line off the reel as they drive broad shoulders into the current and run with a seemingly inexhaustible will after they’ve been hooked.

“With trout, they’ll kind of give up when they get tired,” Hemker said. “Not salmon. They’ll fight all the way to the net.”

Convincing the pre-spawn salmon to eat can often pose the biggest problem, since food is now an afterthought. Conventional wisdom suggests using brightly colored orange and red fly patterns, with imitation eggs serving as the top choice. The color red tends to trigger an attack in many aggressive animals and salmon are no different, instinctively biting and slashing at the perceived threat.

Egg patterns increase the opportunity to catch female kokanees that will often pick up eggs either to move them back to the redds or crush the eggs of competing species, depending upon the theory you subscribe to. For that reason, females are caught more often in the mouth. Although it’s still possible to stick a hook in the corner of their mouths, a corresponding theory holds that males are often snagged by the tail as they attempt to fertilize a fisherman’s fake egg.

One certainty, though, is that egg patterns increase the opportunity to catch large trout that sit behind pods of kokanee salmon and gorge themselves on eggs that are pushed downstream by the current. Big brown trout move up the river in the fall to spawn as well, gladly picking up an opportunistic protein fix along the way and making it difficult to argue the choice of fishing with a bright-colored egg pattern alongside a heavily weighted nymph. Sturdy leaders are required along with aggressive hook sets in order to penetrate a thick, toothy jawbone, and drags set tight.

Then hang on. Once your hooked, you’re in for a wild ride. Without ever even setting foot on an airplane.

Scott Willoughby is a frequent contributor to Colorado Outdoors magazine where this first appeared. This article is copyrighted by the author.

One Response

  1. It has been shown by the latest studies conducted by Brett Johnson of CSU, that Kokanne Salmon make up less than 5% of medium and large sized lake trout. Mr Jonson Studies show that the other 95% percent of there diet is somewhat evenly balanced between Yellow Perch and Rainbow Trout with Yellow perch slightly more than Rainbows. `For 15 years they have been killing lakers. For most of this time the kokanne numbers kept decreasing, or had no real increase. After killing over 6000 lakers at BM they finally changed the bag limit to 5 fish instead of 10, then BINGO! better numbers at the Hatchery. It is the Fisherman who have the insatiable, voracious, and and destructive appetite for kokanne salmon, NOT LAKE TROUT.
    Whole Heartedly,
    Randy Ford

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