The Trout Pool

We fish the waters for trout, but in the end, it is we who are caught by the waters –

David M. Carroll

The Yellowstone Cutthroat Trout and Deep Evolutionary Time

September 19, 2018 – DSG

Yellowstone CutthroatYellowstone Cutthroat Trout – Photo credit to U.S. National Park Service

There is a place high in the Rockies in Wyoming where waters part. Two-Ocean Pass is a national landmark. Here, a small stream called North Two Ocean Creak splits into two waterways on the Continental Divide. The waters of one branch, Pacific Creek, are destined for the Pacific Ocean. The other, Altantic Creek, for the Atlantic Ocean.

This geographic peculiarity, called a distributary (the opposite of a tributary), probably allowed the ancestors of today’s Yellowstone Cutthroat Trout to spread into waters on both sides of the Continental Divide. Long ago a few enterprising young trout explored up what we now call Pacific Creek and somehow ended up on the other side of the hill, in Atlantic Creek. From there they reproduced and a new species was propagated into a new territory.

It is the peculiarities of nature that enable the “butterfly effect” in deep evolutionary time. A landslide changes the course of a creek drainage and isolates a population. Over many thousands of years that population evolves into a distinct sub-species of the original. Two ponds separated by a few feet of flat mud. A fish with extra strong fins manages to flipper its way across that mud into the other pond. Its mutant DNA is passed down to its offspring, and a few million years down the road, the fins morph into legs and the gills turn to lungs.

We can put a number on an immense time scale and claim to understand it. But we as humans cannot actually comprehend the immensity of deep evolutionary time. We try. We do visual exercises where we draw time out on a road. Where a mile of roadway represents the life of Earth, at 4.6 billion years, one million years on that scale is about one foot. Recorded human history (5,000 years) is about one millimeter of that one-mile track.

These visualizations are interesting, but they still don’t really change our brains to perceive a million years of time or more. I hold a rock in my hand and say to my second-grade daughter, “this rock right here might be 500 MILLION years old! Can you believe that?” She seems interested and curious, but she has no personal point of reference to relate, and neither do I.

The trout is a species that seems to easily morph into subspecies based on its environment. Isolated populations living in waterways with light-colored bottoms may evolve lighter colors and fewer spots. Natural selection favors the slightest variation in color between individual trout—the lighter ones ever so slightly more likely to survive predation and pass on their genes.

Humans are in the process of replacing natural evolution with artificial evolution. Gene editing, artificial intelligence, and augmented reality may be the more obvious affronts to nature’s designs. But, what about cars, genetically modified foods (which is almost all food modern humans consume), and medicines that prevent otherwise natural causes of death? Will our evolutionary path be technological? And, if so, what will be our connection to nature as our species increasingly becomes one of human design?


Fish of Paradise

September 8, 2018 – DSG

What is it about the trout that is so alluring?  Many have pondered this question, but I know the answer.  It’s simple.  The trout is a beautiful fish that lives in beautiful places.  There are better tasting fish.  There are those that fight harder.  There are bigger, rarer and more elusive fish.  But, no fish can match the mystique of the mountain trout.  This is especially true of the western backcountry trout.

In summer the western trout glides happily over freestones that give colorful texture to creek beds under a sheen of moving air-water like liquid sunshine.  In fall the trout’s haven may also be adorned with gold as the aspens drop their leaves over the riffles.  Winter conceals silent water sanctuaries under a veil of snow where trout wait in darkness for the coming roar of spring snowmelt, when the creek swells into foaming cataracts under high peaks still clothed in white.

Let me tell you a little story about one of my favorite experiences with a native western backcountry trout.  There was a small lake—a high mountain lake graced on one end by a peaceful dark green conifer forest and on the other by gray-white rockfall fields tumbling steeply down to the water’s edge.  Above and beyond the boulder slopes was a mountain, 14,000 foot plus.  This mountain, from this angle, formed a classic alpine profile.  It had rugged ridges, snowfields, cliff faces and sloping meadows of wildflowers.  It had spiky false peaks and an airy summit that gave it the appearance of a cathedral.

On an early evening in mid-summer the air was calm and the lake surface was flat.  The forested end of the lake looked almost rain-dappled from the rings of many top-feeding trout.  The water was fairly shallow in this area with some submerged logs visible.  Big high-country spruce trees graced the shoreline among the columbines and Indian paint brushes. I cast my attractor pattern a few times but these fish weren’t going to be fooled quite so easily.  Once or twice a twelve-incher moseyed over to take a peek at my presentation only to glide arrogantly away.  No thanks, not good enough. 

I left the serenity of the forest and walked up the shoreline to where the trees ended and the sun-brightened boulders spilled straight into the water.  Here the lake became immediately deep from the shore, the talus continuing its steep slope uninterrupted beneath the water line.

My attractor pattern failed again.  I sat down on a flat whitish boulder and tied two feet of tippet to the hook of my dry fly.  On the end of this tippet went a tiny little nymph or midge–not sure which–but it was small and red.  I stood up and began to false cast, getting some line out, until I could get a good 30 or 40-foot try.  A very slight ripple appeared on the water from a new breeze.

It almost caught me daydreaming when my dry fly blipped underwater.  I gave it a half-second and then, with a smooth motion, raised my rod up to set the hook.  The fish was on, but it didn’t seem like one of those 10-12 inchers I saw in the shallows.  This one had weight.  My rod tip doubled over and line briefly began stripping from my reel as this fish went very deep.  Then there was the unmistakable slow but strong pulse of a heavy fish’s head shake.  The fish then took for the shore straight towards me, as if attacking the source of its sudden struggle.  I reeled fast now to keep the line taut and in moments the fish was almost right under me.  Still, I could see nothing in the dark water—only my strained leader cutting a stiff zigzag at the point of entry.  Finally, a deep red blur appeared dimly from the darkness.  It’s form, colors and size materialized as I pulled it up to the surface and reigned it into my net.

A beauty!  It was a native Colorado River Cutthroat, about 18 inches long and fat, with the brightest red splash down it’s flanks.  I briefly held that jewel of a trout in my hands with the cathedral mountain behind.  Then I eased it back into the lake to watch the glow of red fade back into the watery darkness.  This trout was a privilege to hold and to behold—and to release back into its spectacular home high in the Rockies.