![]() ![]() The best habitat for chum was in the lowest reaches of tributaries or in braided channels in the mainstem river, and some of these areas were cut off by dikes and levees or mined for gravel.Ĭhum faced a litany of other threats to their survival over the years. They have a unique life history, inhabiting shoreline areas where they spawn and rear before going to the ocean. There are many reasons for the precipitous decline, but the loss of freshwater habitat and related ecosystem function arguably is the most important, Todd Hillson, Lower Columbia Chum salmon manager for the Washington Department of Fish and Wildlife (WDFW), told the Council at its July meeting in Vancouver, Washington.Īrtificial spawning channel in Hamilton Creek.Ĭhum spend very little time in freshwater, compared to other salmon species. Columbia River Chum were listed as a threatened species in 1999. But their production is very low, and many of the adult chum that cross the dam fall back over the dam and spawn downstream. Small numbers of chum cross Bonneville Dam each year - generally fewer than 200 fish - and some spawn in tributaries including Eagle Creek and the Wind River. Today, 90 percent of those populations are extinct and the remaining populations, aggregated into a single unit with three components (coast, Cascade, and Columbia Gorge), spawn almost entirely downstream of Bonneville Dam, 50 miles west of Celilo Falls and 146 miles from the ocean. ![]() At one time, there were 17 distinct Chum salmon populations in the Columbia, which spawned from the Grays River near the coast as far upriver as Celilo Falls just east of The Dalles, Oregon. Over time, the Columbia River Chum salmon run has declined by as much as 99 percent, from historic annual run sizes estimated at 500,000 to 1 million fish to modern-day runs ranging from about 1,000 to 10,000 fish. ![]()
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