California sea lion below Bonneville Dam
Columbia River salmon and steelhead face a serious threat from sea lions that prey on fish waiting to move up the fish ladders at Bonneville Dam in early spring. Each year since 2002, sea lions have consumed thousands of migrating fish, many from runs listed as threatened and endangered under the federal Endangered Species Act.
The federal Marine Mammal Protection Act recognizes that predation by a growing sea lion population can jeopardize salmon and steelhead stocks at risk of extinction. After a multi-year effort to haze sea lions away from fish below the dam, NOAA Fisheries concluded that non-lethal measures, by themselves, were not sufficient to curb the growing levels of predation.
In March 2008, Washington, Oregon and Idaho received federal authorization to remove California sea lions observed preying on salmon and steelhead below Bonneville Dam. The federal authorization allows wildlife managers to euthanize sea lions that meet specific criteria, although the states have worked to place those animals in accredited zoos and aquariums whenever possible. Since 2008, state wildlife managers have removed an average of 19 California sea lions a year.
Despite these measures, the number of salmon and steelhead taken by sea lions below Bonneville Dam more than doubled between 2008 and 2015. In response, Congress passed a new law in December 2018 that will provide state and tribal resource managers greater flexibility to manage sea lions in future years.
State fishery managers expect to qualify for permits under that law in 2020. In the meantime, the Washington, Oregon, and area tribes plan to use their existing authority to manage sea lions preying on protected salmon runs in the Columbia River.
In December 2018, the President signed into law legislation that gives state and tribal resource managers more flexibility to manage sea lion predation on Columbia River fish populations.
Senate Bill 3119 allows NOAA-Fisheries to approve permits for Washington, Oregon, and several area Indian tribes that streamline the removal process of a designated number of sea lions from a portion of the Columbia River and adjacent tributaries each year.
The new law gives wildlife managers more flexibility to remove sea lions by:
- Expanding the sea lion removal area both above and below Bonneville Dam. Under SB 3119, sea lions can be removed from River Mile 112 near the I-205 bridge to McNary Dam, and from adjacent tributaries.
- Allowing the removal of Steller sea lions as well as California sea lions.
- Not requiring the stringent procedures to qualify sea lions for removal as the current permit (i.e. identifying individuals by markings, previously hazing them, and documenting predation on salmon or steelhead).
The law does not repeal protections for sea lions provided under the Marine Mammal Protection Act.