Left unchecked, California sea lions could undermine the recovery of threatened and endangered Columbia River salmon and steelhead. For some stocks, recovery efforts have been under way for decades, and funded with billions of dollars in public investment.
Previous experience with California sea lions at Seattle’s Ballard Locks demonstrates the risk these animals can pose to vulnerable fish stocks. From the early 1980s through the mid-1990s, resource managers tried a variety of methods to deter sea lions from preying on Lake Washington winter steelhead. Those efforts were unsuccessful, and sea lion predation continued until the run was effectively destroyed. Today, Lake Washington winter steelhead remain at critically low levels and the population is not expected to recover. With sea lion numbers and predation increasing on the lower Columbia River, fish managers fear some Columbia and Snake River stocks could meet the same fate.
1st of May, 2012