A Historical Look at Salmon
(From top to bottom) Male coho, female coho, male chinook, female chinook.
Drawings by Lisa Miles.
Native Americans have coexisted with salmon in the Columbia basin for millennia. But Americans of European descent have only managed salmon for some 130 years in the "River of the West." In its early stage, salmon management on the Columbia exploited the high-quality spring chinook stocks. R.D. Hume built the first cannery in the lower Columbia in 1866. From 1874 to 1876, the town of Astoria grew from 200 to 2,000 people as the number of canneries and fishermen soared. Harvest peaked in 1895 when 13,800 metric tons of salmon (4–6 million fish) were caught and canned.
By the 1870s, overfishing was already visibly diminishing the Columbia River salmon stocks. Many saw hatcheries as the solution to overfishing; some believed that hatcheries could produce an almost unlimited supply of chinook salmon. Fishermen, cannerymen, and others believed that hatcheries, rather than restrictions on fishing, provided the most desirable solution to boost dwindling stocks.
Fifteen hatcheries operated in the Columbia basin by 1928, releasing a total of two billion fry — mostly spring chinook -into the Columbia. Hatcheries aimed to gain control over the production of salmon in the Columbia and to maintain high fish production in the face of intensive harvest.
The most significant effect of hatcheries before 1930 may have been to undervalue other forms of management, such as habitat protection or restoration, because hatcheries were considered adequate, even preferable, substitutes for lost habitat.
Hatcheries have been the dominant management strategy in the Columbia basin since 1930. Before 1981, hatcheries received the largest component (43 percent) of the total budget for salmon management in the basin. From 1981–91, hatcheries received 40 percent of the $1.3 billion spent on salmon management in the basin. In contrast, less than 1 percent of the salmon management budget was spent on habitat restoration prior to 1981. Since then, the share has risen to 7 percent.
It is clear that hatcheries have failed to maintain salmon production in the face of overharvest and habitat degradation. The 19th century salmon run in the Columbia was estimated at between 10–16 million fish; today it is about 900,000 fish, a decline of more than 90 percent. Depleted stocks and degraded stream systems have dramatically reduced natural reproduction throughout the basin.
As a result of the declining harvest and diminishing returns, hatchery management has undergone a reappraisal. Current management philosophies consider hatcheries as one of many tools for the restoration of depleted salmonid stocks, rather than virtually the only tool. Recently the Independent Science Group called for better integration of natural and artificial production systems in a more comprehensive management strategy at the level of the watershed or sub-basin. Redefining the role of hatcheries is one of the most important issues in Columbia River salmon management.
Habitat restoration has received far less attention than hatcheries, but its history is no less complex. The first significant efforts to restore salmon habitat began with the Civilian Conservation Corps (CCC) in the 1930s. Mostly, the work entailed placing a variety of structures, primarily made of wood or boulders, into the stream channel to create fish habitat such as pools or spawning gravel. Although seldom explicitly stated, the reasoning behind this work seemed clear. Biologists examined the general life-history of a particular species such as coho salmon and determined the factor limiting production. In the case of coho salmon, the volume of pools or spawning gravel were usually considered the limiting factors. Few of these efforts were evaluated carefully.
This approach assumed it is possible to adequately treat the effects of habitat degradation throughout the watershed while working only in the stream. This assumption is false. This type of habitat work has not fixed the problems caused by habitat degradation. While numbers of young salmon rearing around the instream structures increased in a few cases, these results were short-lived. In most cases, projects were not evaluated well enough to determine if they were in fact having the desired effect, or even whether the structures lasted. The result: over 200 stocks of salmon in the Northwest have declined to the point that we must take action to ensure their survival.
How did it happen that almost four decades of in-channel work was largely for nought? How do we ensure that the same problem does not recur four decades from now? Hindsight shows the traditional approach failed for a number of reasons.
The traditional approach focused on the habitat unit, a focus as fine as an individual pool, or possibly a short section of stream. While small gains might be made in one area of the watershed at this modest spatial scale, other areas might be subject to severe impacts, resulting in a net loss of salmon spawning and rearing in the basin. By neglecting larger watershed, landscape, and regional scales, the traditional approach overlooked the nature and degree of more widespread degradation.
The tapestry of the landscape changed, but traditional approaches to salmon restoration didn't. The approaches have become increasingly illsuited to a landscape dominated by intensive logging. As recently as the 1960s, the forested landscape was generally intact, with islands of degradation such as clearcuts scattered here and there. By the 1990s, after. more than a decade of intensive timber harvest, the landscape has been rendered a patchwork of roads and clearcuts, in which intact patches have become the exception rather than the rule. As good habitat has decreased, the remaining intact areas have become important centers of biological production. But the physical separation of these areas has turned some specific salmon life-history strategies into death traps, because the fish cannot necessarily move from one refuge to another to complete their life stages.
As we begin to devise a new framework, these observations become important. Failure to appreciate habitat dynamics and faulty instream structures did not cause the decline of Pacific salmon, but they did contribute to their demise.
Thomas C. Dewberry works as a restoration ecologist for Ecotrust to analyze, oversee, and implement various landscape and habitat restoration projects. Restoring the River: A Plan for the Chinook Watershed was published by Sea Resources and Ecotrust in September 1997 and is now out of print.