Native Trout of North America - PRINTS
Posted by Nick Amato on
We tend to think of the landscape around us, our visible world, as permanent and indestructible—the "eternal hills" of the poets, so to speak. Actually, what we see are transient landforms, everchanging over eons on a scale unimaginable.
Ever since the earth's crust hardened there have been periods of cataclysmic convulsions: shearings, thrustings, foldings and tiltings, with upwellings of magma spouting forth as volcanoes or passive fissure flows, forcing segments of crust along zones of weakness and stress to manifest as mountain ranges, valleys or awesome trenches under the sea.
No sooner had the continental crust been elevated into domes and ridges than the forces of destruction took over. Rain, running water, frost and wind began the slow transport of the detritus to lower levels, the valleys and the sea. Once the crust was base leveled, the sea encroached upon the lowlands and vast deposits of sediment accumulated, finally becoming sedimentary rocks, their tremendous weight triggering further adjustments of the crust and starting the process all over again—the new building on the stumps of the old.
The planetary paroxysms appear to have occurred in ordered sequence, the slow "rhythm of geological time," separated by a quarter billion years with intervening periods of minor uplifts, each followed by a glacial period. There have been at least four of these major mountain forming epochs and we live near the close of the last one, when the uplands are still high, carved into jagged crests and peaks by glacial ice. In fact, the last glaciation is still with us; there is enough water locked up in present land ice to raise the sea level two hundred feet or more, should it all melt.
Moreover, the crust is still shifting about as molten magma deep within the earth upwells in convection currents, jostling tectonic plates against each other, causing earth tremors and vulcanism. In the Cascade Mountain Range in Washington state, the eruption in 1980 of Mount St Helens blew 1,300 feet off her peak in response to such internal pressures, scattering volcanic debris far and wide in a cataclysmic explosion that devastated forest lands, obliterated lakes and laid waste over 150 miles of prime trout and salmon streams. St. Helens has done this several times in the past, her last previous eruption occurring in 1842. Yet after each holocaust the surrounding streams purged themselves of ash and mud flows and the trout and salmon populations re-established themselves.
There are hundreds of other volcanoes in the "ring of fire" girdling the Pacific, some believed to be "extinct; others quite active and still smoldering, biding time until pressures build up to force eruptions. Those of us who live in the Pacific Northwest dwell In their shadows as witnesses to what has happened in the past and predictors of what is likely to occur in the future.
Even though our time coincides with the close of the last great epoch of uplift and distortion, there are still adjustments being made as continental blocks seek to attain equlllbrium with surrounding masses and the upwelling of molten magma from the depths continues to drag the tectonic plates around like pans of shifting pack ice in the Arctic Sea.
If it were not for the mountains extending high Into the heavens, the planetary winds would circle the globe unobstructed and the weather would not be worthy of discussion. The climate would be uniform, monotonous, varying only with latitude and whether oceanic or continental. But the mountain bariers have changed all that, diverting the even flow of air, causing eddies and cross currents, forcing It upward, cooling it and causing condensation of water vapor to fall as rain or snow. Thus we owe our present diversification of climates to the past convulsions of the earth's crust, which has made possible the multitude of microclimates and ecological niches found In mountainous regions; where we may find a rain forest on one side of a range and a desert on the other.
The aggregate impact of these past events has shaped the destinies of all living things. Some, unable to adapt to the vast changes, became extinct. Others, more suited to survive the changes in their environment, prospered and evolved into new genera and species. The process continues. Since these slow changes do not seem to account for the mass extinctions such as befell the dinosaurs and mammoths, it is theorized that other cataclysmic events as yet undetermined must have occurred.
Of all evolving living creatures, the fishes of the sea were the least affected by the geological events that were altering the face of the globe. The oceans respond more slowly and to a lesser degree to climatic changes wrought by crustal upheavals and provide a much more equitable environment for marine life than the often harsh conditions the continents offered to land-based creatures. Consequently, evolutionary changes in sea creatures have been slower and less drastic than in land animals and as a result there are still many primitive types of fish in existence today. One such fish, a "living fossil," was hauled up off the African coast in 1938 and christened Latimeria, a member of the coelacanths which were thought to have been extinct since the Cretaceous Period 60 to 100 million years ago, a time when dinosaurs still trod upon the earth.
The salmonids are also a primitive type of fish in form and structure with the earliest known fossil records going back 40 to 60 million years ago to the Eocene Epoch. As cold water adapted fish, trout and salmon probably evolved in the Arctic, possibly 10 million years ago, when the climate of that region resembled that of our temperate zone today. Shortly thereafter the ancestors of the European brown trout and Atlantic salmon may have become isolated from the ancestors of the trout and salmon of the North Pacific region. It is thought that North America was the place of origin of these western trout and salmon and that they became established in eastern Asia by way of the Bering Land Bridge which appeared at intervals during the last glacial epoch.
Before vulcanism built up the Cascade Range and well before the last glaciation, a giant saber-toothed salmon and a trout called Rhabdofario found a home in what are now the desert basins of eastern Oregon, leaving their fossils buried in sediment. Although Rhabdofario became the common trout of western North America during the Pliocene Epoch immediately preceding the last glacial period, it is not known exactly when or from what ancestors our modem trout evolved.
Probably the first of the present races of trout to become established on the Pacific Slope was the Mexican golden trout, the probable progenitor of the Apache and the Gila trout. The Mexican golden trout may also have been a remote ancestor of the redbands and rainbows which later displaced It except In a few headwaters draining out of the Sierra Madre.
The first modern trout to Invade the waters of the Pacific Northwest, however, was the cutthroat, and it became established in waters denied latecomers by the formation of impassable barriers. Next on the scene In the Northwest were the redbands, which displaced the cutthroats of interior drainages below the barriers in most places. Finally the rainbows appeared and displaced the redbands where they came In contact.
Thus the geological upheavals of the past built vast mountain ranges, leveled the plains, re-arranged the drainage patterns and altered the climate which in turn was responsible for the glaciation that sculptured the high country and accelerated the tearing down processes. All of these actions and Interactions have merged to create the myriad ecological niches that now exist, each with Its own distinctive plant and animal communities. These are particularly abundant and varied In western North America, resulting In the richest trout fauna in the world, for it is microhabitats that are responsible for the reproductive isolation that is the guiding force in evolving species and subspecies, cut off from the gene flow of the parent race by physical or thermal barriers. Here trout occur throughout five separate life zones—from Upper Sonoran to Arctic Alpine.
In all of North America there are five recognized species of native trout with thirty-one subspecies, as well as five species of charr, with thirteen subspecies, by my count. Each evolved to its present state of perfection by responses to particular environmental pressures. Some of these are as yet formally undescribed, two are extinct, while another is extinct in pure form. What remains today as a legacy to that once abundant and widespread pristine world of native trout—particularly in interior drainages—are scattered remnants hanging on precariously in a few remote headwater streams. In roughly 100 years man has practically destroyed that which took natural processes millions or years to create. The degradation of the waters by poor forestry practices, overgrazing, channel blocking dams, water diversion and pollution have all contributed to the decimation of native trout populations, but the crowning indignity, the coup de grace, was the introduction of non-native trout resulting in the displacement of natives either through competition or hybridization. It is now a common experience to fish a beautiful mountain stream and catch almost every kind of trout under the sun-except a native! Some anglers and fisheries officials do not seem concerned about this, as long as there are plenty of trout to be caught... any kind of trout. It is for those of us who do care, who value quality over quantity and hope for the return of the "native" that I have written this book.
—Robert H. Smith (from his Prologue 1994)
PUBLISHERS NOTE: The book "Native Trout of North America" is no longer in print. However, you can order the amazing water colors painted specifically for the book and approved by Robert H. Smith himself.
