Cycles in Ocean Productivity, Trends in Habitat Quality, and the Restoration of Salmon Runs in Oregon

Abstract

Abstract Conservation management is always a political, as well as a biological, problem. Oregon's coastal natural coho salmon (Oncorhynchus kisutch) populations have drawn political attention because abundances are at critically low levels. One of the underlying problems is a long-term trend of habitat degradation. In addition, decadal-scale cycles in ocean survival of coho salmon may lead to cycles in abundance that are independent of freshwater habitat trends. Programs to restore coho salmon populations through stream restoration will take decades to produce long-lasting results. When population abundance varies widely over time, a rise in abundance following the initiation of recovery measures can be taken as an indication of success even when the increase in numbers was independent of the actions taken. Support for recovery efforts must be sustained through the cycle of higher abundance. The true measure of success for such projects is the continued survival of the population through subsequent episo...