The Columbia River Basin
Geology and Climate
The Columbia River drops more than 735 m from its headwaters in British Columbia, winding over 1,950 km to the Pacific Ocean. Although the river itself flows from Canada through only two states, forming part of the Washington-Oregon border, the vast Interior Columbia River Basin is defined by the area drained by the river and its many tributaries. This 58-million-hectare area (about the size of France) extends roughly from the crest of the Cascade Mountains of Oregon and Washington east through Idaho to the Continental Divide in the Rocky Mountains of Montana and Wyoming, and from the headwaters of the Columbia River in Canada to the high desert of northern Nevada and northwestern Utah.
The Columbia River Basin is a complex tapestry of mountains, high plateaus, desert basins, river valleys, rolling uplands, and deep gorges woven together by the Columbia River and its tributaries.
Mountains are a major and dramatic presence in the Columbia River Basin. There are a number of mountain ranges in the basin, including the volcanic Cascades forming the western border and the Rocky Mountains on the basin's eastern border.
South and east of the Cascades are the Klamath Uplands, which support lodgepole pine and juniper forests. The Columbia Plateau ecosystem, an old basaltic lava field, consists of a variety of grasses and shrubs. The remote Owyhee Uplands include mountains and a rolling plateau transected by deep canyons and covered by sagebrush, bunchgrasses, and junipers. The upper Snake River floodplain supports cottonwoods and grasses. Irrigated croplands dominate many valleys, plateaus, and uplands. The northern reaches of the arid Great Basin ecosystem consist of sagebrush, bitterbrush, and rabbitbrush at lower elevations.
A common feature of the Columbia River Basin is the shrub-steppe ecosystem where moisture is scarce (coming mostly from snow in winter), the wind is persistent, and temperatures vary from 38C in summer to well below freezing in winter.
Big sagebrush is especially adapted to survive these conditions. Its root structure can reach as far as 27 m in diameter, dominating the water source and limiting the number of other large plants that can establish themselves. Its small gray-green leaves are covered with minute white hairs that keep water in the plant. In this harsh climate, sagebrush provides important cover and forage for wildlife.
Accompanying sagebrush in the community are a variety of native plants such as rabbitbrush, bitterbrush, greasewood, winterfat, spiny hopsage, horsebrush, fescue, Indian ricegrass, bluebunch wheatgrass, and wildrye. Other herbaceous plants, or forbs, include lupines, globe mallow, Indian paintbrush, sego lilies, phlox, and arrowleaf balsamroot. An occasional prickly pear cactus can also be found.
Fish and Wildlife
The Columbia Basin's deserts, forests, rivers, and rangelands provide integral habitat for 609 known fish and wildlife species, including some of the most rare and endangered species in North America: bull trout and sockeye salmon in the rivers of Oregon, Washington, and Idaho; bald eagles and vesper sparrows throughout the basin; gray wolves, grizzly bears, and even the elusive Canada lynx in remote areas of Idaho and northwestern Montana.
Close to 3,800 invertebrate species have been identified in the basin, but an estimated 20,000 more-including various species of ants, spiders, and butterflies-are yet to be described. Millions of migratory birds rest and feed in various wetlands and forests within the basin. The Snake River Birds of Prey area near Boise, Idaho, harbors the densest nesting concentration of birds of prey in North America, including more than 800 pairs of eagles, falcons, hawks, owls, and other raptors.
Oasis in the Desert
One of the premier birdwatching sites in the United States is found in an unlikely spot-the remote high desert of Harney Basin in southeastern Oregon. Here, snowpack from the Steens Mountains drains into a complex system of landlocked lakes, marshes, and waterways at the Malheur National Wildlife Refuge. These wetlands attract thousands of migratory birds each year, representing over 300 species.
Few things link the Columbia Basin like anadromous fish. These fish reproduce and rear in fresh water, then migrate downriver to the ocean. As adults, they return to the streams and rivers where they hatched to start the cycle over again. Some anadromous fish travel over 1,440 km on this journey, returning to the exact location where they hatched.
wildlife and good fishing attract people to the Columbia River
Basin. A. Lynn Burton, USFS
The varied wildlife and good fishing attract people to the Columbia River Basin.
A. Lynn Burton, USFS
The wetlands of Malheur National
Wildlife Refuge in arid southeastern Oregon make this a favorite
stopover and feeding site for birds. Beth Ullenberg, USFWS
The wetlands of Malheur National Wildlife Refuge in arid southeastern Oregon make this a favorite stopover and feeding site for birds.
Beth Ullenberg, USFWS
For thousands of years, salmon have played an important cultural role for the people in the Columbia River Basin, not only as a keystone species and food source, but also because of their awe-inspiring life cycle. As a result, restoring historic salmon runs has been a driving force behind many recent management initiatives in the basin.
Just as salmon cross jurisdictional boundaries, so do many of the issues faced by land managers in the basin. The spread of weeds, wildland fires, disease spores, stream silt, and air pollution, as well as the loss of migratory bird habitat, all clearly cross land-ownership boundaries.
To ensure these issues are adequately addressed, federal agencies are working together to develop a scientifically sound ecosystem-based strategy for managing 28 million hectares of public lands in the Interior Columbia River Basin. This far-reaching effort, the Interior Columbia Basin Ecosystem Management Project, seeks to restore and maintain healthy ecosystems and support the economic, social, and cultural needs of people and communities.
The project's first step was to conduct an unprecedented study of the entire area. The result was The Integrated Scientific Assessment for Ecosystem Management in the Interior Columbia Basin and Portions of the Klamath and Great Basins, published in September 1996. This comprehensive scientific analysis involved scientists and technicians from federal and state agencies, universities, and private contractors who examined changing conditions in the basin over the last 100 years. They confirmed that the Columbia River Basin has undergone dramatic ecological changes as the region has been settled and developed.
A hundred years ago, the basin featured large, widely spaced, sun-loving trees. Frequent, light fires cleared competing vegetation. Plant and animal species migrated freely through large blocks of habitat. Over the last century, harvesting of large old-growth trees resulted in forests with smaller, densely grown, shade-tolerant trees. As trees became crowded, increased competition for water and nutrients made them susceptible to damage from insects and diseases. In addition, historic suppression of fire allowed shade-tolerant species to fill the understory. This provided a fuel ladder to the taller trees, increasing the likelihood that wildland fires would be severe and costly.
The Bureau of Land Management (BLM) and the U.S. Forest Service are now using prescribed (carefully managed) burning to reintroduce fire into the ecosystem in order to avoid catastrophic wildland fires. They also are experimenting with ways to use forest thinning and various timber harvest techniques to reduce fuel loads.
Wildland fires also historically cleared organic debris from the rangelands, killed nonsprouting species such as sagebrush, and stimulated regrowth of sprouting shrubs and grasses. However, roads and agricultural lands stopped the spread of fire, and people suppressed fires whenever they could. As a result, fire frequency decreased. The lack of fire has allowed woody species such as juniper to encroach upon native perennial grasses and forbs.
In addition, heavy grazing by livestock at the turn of the century significantly altered rangeland plants. Overgrazing of riparian (streamside) areas resulted in unstable streambanks, increased stream sedimentation, and reduced some areas’ ability to capture and store water. Undesirable nonnative species of plants such as cheatgrass and medusa-head rye have invaded sagebrush ecosystems, outcompeting native grasses and forbs and reducing forage and cover for wildlife and livestock. The reduction in native species has created a more simplified and less resilient rangeland ecosystem.
Local ranchers, environmental organizations, and government agencies
are working together to reverse these trends. In the Trout Creek Mountains
in southeastern Oregon, for example, these partners altered grazing
practices to repair damage caused by more than 100 years of season-long
grazing. Their efforts are leading to ecosystem improvements, most notably
measured by an increased in threatened Lahontan cutthroat trout inhabiting
Nonnative Weed Invasions
The spread of invasive, nonnative (exotic) plants is causing severe damage to entire ecosystems in the Columbia River Basin. In addition to cheatgrass and medusahead rye, leafy spurge, spotted knapweed, rush skeletonweed, and yellow starthistle are spreading rapidly into rangelands, forestlands, recreation areas, roadsides, and waterways in eastern Oregon, eastern Washington, western Montana, and Idaho.
BLM Weed Demonstration Areas within the basin demonstrate how people can work cooperatively to prevent and control weeds. For example, where Idaho, Oregon, and Washington meet just north of the famous Hell's Canyon, a community team representing state and local government as well as private industry worked side-by-side to map and inventory over 8,000 hectares that were highly susceptible to broad-scale degradation from nearby massive invasions of yellow starthistle.
The health of aquatic ecosystems is critical to the entire Columbia River Basin. About 80 percent of all fish and wildlife in the basin use the riparian (streamside) habitat at one time or another. Timber harvesting, livestock grazing, road construction, and mining have all dramatically changed aquatic ecosystems, affecting both water quality and quantity and altering water flows and temperatures. This, in turn, affects the types of wildlife, fish, and plants that can survive in the area.
Dams restrict the migration of anadromous fish species, blocking them from important habitats and increasing mortality of juvenile salmon traveling downstream. Some of these dams have fish passage facilities, but many smaller dams do not. Turbines kill juvenile fish. Dams also cause migrating fish to spend more time in slower and warmer waters created by reservoirs. Physiological stress and increased susceptibility to predators result as fish congregate in smaller areas.
Public and private water managers are working to increase the survival of these fish by increasing water flows during certain times of the year to help fish travel over the dams, installing fish ladders to guide fish around the spillways, and hauling juvenile fish around dams in trucks or barges. Despite these efforts, however, dams still pose the greatest threat to the survival of native salmon and trout runs in the Columbia River Basin.
Loss and fragmentation of diverse habitat have also contributed to a decline in native fish diversity. Many salmon species inhabit a small portion of their former ranges, while many introduced nonnative species, including recreational species such as bass and brook trout, are widespread. Of 87 native fishes in the basin, 45 are recognized by state and federal management agencies as sensitive or species of special concern. Twelve species are either listed or candidates for listing under the Endangered Species Act, including bull trout and steelhead.
Aquatic Restoration Efforts
Local communities, including schools, are working with land managers on a number of aggressive aquatic habitat restoration efforts throughout the Columbia River Basin.
In central Oregon, for example, two teachers are involving students with ongoing watershed restoration efforts on the Crooked River, which winds through the Ochoco Mountains and the Columbia Plateau. With community support and financial assistance from organizations such as Bring Back the Natives, a national public/private initiative to restore native aquatic species, the teachers created a watershed-level environmental education program for K12 students in two school districts. The program draws on local experts who offer technical and financial assistance. In return, students provide the community with watershed restoration work and research. High school students have completed sediment studies, habitat surveys, and wild fish monitoring projects. Students also work on stream restoration and riparian plantings through a special greenhouse program to propagate cottonwood trees.
Habitat Loss in Grasslands and Forests
The loss of steppe habitat (areas receiving less than 30 cm of rain per year) in the Columbia River Basin is having a detrimental effect on wildlife. Populations of both grassland and shrub-steppe species such as the sage-grouse, Columbian sharp-tailed grouse, sagebrush vole, upland sandpiper, grasshopper sparrow, and pronghorn are declining throughout the basin. In eastern Washington, the BLM and the Washington Department of Fish and Wildlife are working together to assist upland species such as sharptail and sage grouse by exchanging land with private landowners to acquire steppe habitats in large blocks. Much of the native steppe habitat has been converted for agricultural purposes. By exchanging isolated forested tracts and purchasing larger blocks of meadow steppe lands, the agencies hope to provide a safety net of habitat.
In the basin's forests, populations of cavity dwellers, including several species of owl, woodpeckers, and the northern flying squirrel, are declining due to fewer dead or dying trees. In areas near roads, fallen trees are often collected for firewood or other uses. Roads also pose other risks to wildlife. Many animals have been killed crossing busy roads and highways.
Neotropical migratory birds traveling between North and South America each year also have fewer and fewer safe stopover areas. Habitat is also an issue for the federally protected grizzly bear and gray wolf, which require large, uninhabited areas. Their needs and the needs of people living near them must be carefully weighed in planning for their recovery.
A New Management Approach
The Scientific Assessment confirmed that rangeland, aquatic, and forest health issues are intricately connected in the Columbia River Basin. Scientists concluded that any proposed management strategy must also link these issues across boundary lines and agency jurisdictions.
A proposed strategy is described in two draft environmental impact statements released in June 1997. It calls for aggressive restoration of forests, rangelands, and watersheds. It emphasizes forest thinning and using prescribed fires during cooler seasons to decrease risks of large, severe wildland fires. It also calls for increased efforts to stem the tide of invasive weeds. The proposed strategy recognizes that people who live in the basin have a stake in its management many make their living from its rich natural resources. Although most of the basin is rural, several urban centers are among the fastest growing in the country. In addition, a number of Native American tribes and other traditional communities have interests in lands within the basin.
Monitoring watershed conditions at many different scales will be a
key to measuring progress as National Forests and BLM Districts in the
Columbia River Basin begin to implement this plan. Monitoring tools
include looking at changes in water quality and quantity, streamside
vegetation, extent of weed invasions, native fish and wildlife populations,
and numbers and sizes of severe wildland fires. But the ultimate measure
of success will be known many years from now, when people living in
the basin continue to enjoy a high quality of life, sustained by the
basin's rich natural resources. With their involvement and support,
federal, state, and private scientists and land managers hope to restore
ecological health to the basin so future generations will continue to
be captured and enraptured by its wild beauty.