In 1805, when Captains Meriwether Lewis and William Clark reached the western end of their remarkable journey across the United States, they deemed coastal Oregon a miserable place to spend a winter. Pacific Ocean rainstorms pounded their Fort Clatsop encampment, and they suffered the penetrating, wet cold that no thermometer can measure. Tired not only of the weather, but also of the dried salmon provided by Clatsop Indians, they longed to head home to the East. Impatience led them to attempt a nearly disastrous early departure back across the Rockies.
Clark’s despondence comes through in his journal entry: "It would be distressing to a feeling person to See our Situation in this time all wet and cold. . . ." Later, he referred to the source of this weather: ". . . in Sight of the Great Western (for I cannot say Pacific) Ocian [sic] as I have not Seen one pacific day Since my arrival in its vicinity."
 Two hundred years later, Oregon and the Pacific West have changed dramatically. Not the weather, but the landscapes beheld by Lewis and Clark and their small expeditionary group (dubbed the Corps of Discovery by President Thomas Jefferson) have been transformed in all too familiar ways. We’ve logged our coastal forests extensively, and put our interior dry forests at risk of catastrophic fire, paradoxically due to a public policy of fire suppression during the last century. We’ve overstocked our rangelands, damaging and destroying riparian habitat. We’ve bottled up our rivers and streams with dams and channels, converting them into slow-flowing lakes. Consequently, the abundance and diversity of wildlife have declined. And so, with the opening of a new office of the Wildlife Conservation Society (WCS) in Portland, Oregon, and as our nation turns its attention to the bicentennial celebration of Lewis and Clark’s expedition, we find ourselves poised to address an urgent challenge. Our mission: to understand how best to conserve wildlife and wild landscapes in this decidedly not miserable, but wondrous part of North America.
A starting point is to consider how weather and geography have shaped the region’s distinctive wildlife and habitats. In winter, heavy storms soak valleys and dump snow in the high Cascades. Winter rain and spring snowmelt fill the Columbia River, triggering the migration of salmon. The mountains create a strong rain shadow, so that, within just a few miles, temperate rain forest gives way to dry forest and cold desert. Summer and fall unfold dry and clear (a fact Oregonians like to keep to themselves). Winter precipitation followed by summer drought produce the world’s greatest diversity of coniferous trees; conifers continue to grow in the cool, but typically not freezing, winter weather, while deciduous heartwoods lie dormant. The mighty Columbia traverses these landscapes and once gave vast numbers of Pacific salmon access to spawning grounds as far inland as the Grand Tetons and British Columbia. Grizzly bears and wolves, wiped out in the American Pacific West, depended on salmon or on the wildlife that fed on salmon. Large populations of beavers dammed streams and small rivers in both wet and arid areas. Woodpeckers and other birds teemed in the diverse forests dominated by large trees. The landscapes that Lewis and Clark described were shaped by the dynamic action of rivers and streams, and the forests were shaped by fire. These processes sustained wildlife and wild lands in the Pacific West. And so, my WCS colleagues and I have learned that the key to wildlife conservation here is to restore and work with the natural life cycles of streams and forests.
When listing the new birds that he found, Lewis wrote in his journal of ". . . a black species of woodpecker about the size of the lark woodpecker." It came to be known as Lewis’s woodpecker. This and many other birds of western forests depend on decaying snags (standing dead trees often killed by low-intensity fires) for food and shelter. Insects thrive in snags and provide food for the birds. The excavations made by woodpeckers in the decaying wood become nest cavities for other animals. Fire suppression disrupts these processes. It also results in dense, shrubby growth in the forest understory, which heightens the risk of more intense, large-scale fires that leave vast areas devoid of trees.
In particular, we have uncovered complex interrelationships among woodpeckers, fire, bark beetles, and wood-decaying fungi. Historically, ponderosa pine forests experienced frequent low-intensity fires, which cleared out underbrush and small trees and created an open, park-like appearance—a rare sight today. Light fires also weakened some trees, attracting bark beetles in great numbers. The beetles overwhelmed the trees’ defenses, resulting in death. Woodpeckers discovered these newly created snags, and bored deep into the trunks to go after developing beetle larvae.
It turns out that the key to cavity excavation is the presence of sapwood decay fungi, which softens the wood enough for woodpeckers to penetrate it. Woodpeckers have wood decay fungi present on their beaks, and probably transfer fungi from snag to snag as they forage on bark beetles. Abandoned by the woodpeckers, cavities eventually become homes for flying squirrels, bats, western bluebirds, nuthatches, and many other animals. By deliberately setting prescribed fires in ponderosa pine forests, we can therefore both help wildlife and reduce the possiblity of a fierce, out-of-control fire that could destroy critical wildlife habitat and endanger human life and property.
In the accounts of their expedition, Lewis and Clark made several mentions of wildlife abundance in the West, and invariably American beavers are included. The Corps ate beavers throughout their trip. Lewis once noted, "the beaver was large and fat; we have therefore fared sumptuously today." Beaver decline and local extinction have occurred widely throughout the West, following a long history of fur trapping and a more recent history of removal as a pest species. Beavers, however, are excellent ecosystem engineers. They repair degraded streams and reinvigorate water tables and woody vegetation. In areas of southwest Wyoming where beavers have been reintroduced, more beaver dams and beaver ponds mean more habitat for migratory songbirds. Elsewhere, in northern California on private ranch land and central Oregon on Bureau of Land Management land, we have restored streams and allowed woody vegetation to regenerate by carefully regulating cattle grazing. More vegetation likewise enhances and increases habitat for migratory songbirds, including yellow warblers, yellow-breasted chats, and willow flycatchers.
"The number of dead Salmon on the Shores & floating in the river is incrediable [sic] to Say," Clark wrote. Little could he know that the Pacific West ecosystem depends on the abundance of salmon. Salmon grow large in the Pacific Ocean and return to thousands of streams to spawn and die. Many wildlife species directly consume spawning salmon, of course, but recently we have recognized the importance of the marine nutrients that decaying salmon contribute to terrestrial ecosystems. These nutrients filter through food webs: nourishing both aquatic insects that, in turn, feed songbirds and young salmon, and riparian vegetation that feeds browsing deer and moose. The decline of salmon runs goes hand in hand with declines of other wildlife. WCS is working with the Tlingit First Nation people in British Columbia and others to understand such linkages on the Taku River, a largely intact ecosystem with abundant salmon, grizzly bears, eagles, and wolves. We hope to understand how such systems work so we can figure out how to restore our declining natural cycles—an effective and cost-efficient way to bring about widespread wildlife conservation.
"Ocian in view! O! the Joy," exclaimed Clark as they neared the Pacific. Two hundred years later, there is indeed great joy working in my native Oregon, even with the rain.
Steve Zack coordinates conservation efforts in the Pacific West for the Wildlife Conservation Society’s North America Program.
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