Washington Dept. of Fish and Wildlife

Columbia River
Sea Lions
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News
Sea lion relocation efforts suspended - May 5, 2008
Sea lion succumbs during health exam- Apr 29, 2008
Sea lion relocation to begin tomorrow (April 24)- Apr 23, 2008
WDFW to take public comments on proposed sea lion removal- Mar 18, 2008
NOAA Says Three States Can Remove Sea Lions That Threaten Salmon- Mar 18, 2008 [PDF format]
Draft EA on States’ Request for MMPA Section 120 Authorization - Jan 17, 2008
Early hazing will help protect white sturgeon- Dec 04, 2007
Task force recommends lethal removal of California sea lions - Nov 02, 2007 [PDF format]
Background
WDFW statement
Questions and Answers
Sea Lion Fact Sheet
Predation at Bonneville
Endangered/Threatened Fish
Section 120 Application
[PDF Format]
Recent Federal Action
Other Voices
Columbia River Inter-Tribal Fish Commission letter
[PDF Format]
Northwest Power and Conservation Chair letter
In The News
Deadly force should be option against sea lions
Tacoma News Tribune editorial, April 23, 2007
Stop feeding salmon to the lions
Oregonian editorial, April 19, 2007
No free lunch on the Columbia
Oregonian editorial, April 13, 2006
Get the Lions Off the Fish Ladder
Oregonian editorial, April 18, 2005
Related Links
Oregon Dept. of Fish and Wildlife
Idaho Dept. of Fish and Wildlife
National Marine Fisheries Service
US Army Corps of Engineers
Fish Counts at Bonneville Dam
Northwest Power and Conservation Council
Marine Mammal Protection Act


California sea lion below Bonneville Dam

Questions and Answers: Columbia River sea lions


1) Why are California sea lions a concern on the Columbia River?

On the Columbia River, a robust and growing population of California sea lions is preying on endangered and threatened stocks of salmon and steelhead that are listed for protection under the federal Endangered Species Act (ESA). Sea lion predation is occurring throughout in the lower river system, but the problem is especially acute below Bonneville Dam where returning salmon and steelhead congregate as they prepare to move up the dam’s fish ladders to spawn upstream.

Fish managers are also concerned about increasing predation by sea lions on mature sturgeon below Bonneville Dam and on listed salmon and steelhead runs in the Willamette River and other tributaries to the Columbia River. Human safety is also a concern. In recent years, there have been numerous reports of these powerful animals swamping boats and biting people along the Pacific coast.

2) Are California sea lions native to the Columbia River?

California sea lions are found all along the west coast of the North America from Mexico to southeast Alaska including the mouth of the Columbia River. However, in recent years their numbers and distribution have increased significantly in the Columbia River system all the way upriver to Bonneville Dam. Until the early 1980s, it was uncommon to see a California sea lion in the Columbia River. Since then, migrant animals from California and Mexico have appeared in the river seasonally from January to late May in dramatically increasing numbers – first in the river estuary, then in the tributaries and finally upriver to Bonneville Dam, 145 miles from the river mouth. A 2006 survey conducted by the Washington Department of Fish and Wildlife (WDFW) estimated up to 1,200 California sea lions and 1,000 Steller sea lions in the lower Columbia River.

California sea lions are a distinct species from Steller sea lions. Unlike California sea lions, Steller sea lions are present year-round in the Columbia River, but seldom move upriver past the mouth of the Cowlitz River at Longview (River Mile 70). The Steller sea lions’ diet relies more on marine fish than on salmon and steelhead. Steller sea lions are not a target of lethal removal efforts.

3) What fish are at risk from sea lions in the Columbia River?

The population of greatest concern is the Upper Columbia Spring Chinook run, which is listed as endangered under the Endangered Species Act (ESA). Snake River Spring/Summer Chinook, listed as threatened under the ESA, are also highly vulnerable to predation by sea lions feeding in spring immediately downriver from Bonneville Dam. Other ESA-listed salmon and steelhead populations passing through the lower Columbia River when sea lions are feeding include Lower Columbia River Chinook, Lower Columbia River steelhead, Middle Columbia River steelhead, Snake River Basin steelhead, Upper Willamette River Chinook and Upper Willamette River steelhead. All are listed as threatened under the ESA.

4) Are other impacts to ESA-listed salmon and steelhead being addressed?

Yes. There has been an extraordinary and growing effort in this region to protect and recover salmon and steelhead populations. Recovery plans are being developed in every watershed to restore important habitat, improve dam passage survival, reform hatchery programs to assist wild fish populations, and reshape fisheries by focusing on selectively harvesting healthy, hatchery fish. The people of the Northwest have supported restoration efforts, and borne the costs, because of the importance of salmon to our heritage, the cultural value to Native Americans, and the economic value of salmon to our fishing communities.

5) How do fish managers know that California sea lions are preying on protected fish?

Since 2002, the Army Corps of Engineers has recorded the number of salmon and steelhead consumed by California sea lions annually from January through May immediately below Bonneville Dam. In 2005, for example, the Corps watched sea lions consume 3,023 fish in a year when ESA-listed upriver chinook stocks made up 14.5 percent of the run.

Besides recording the number of fish taken, the U.S. Army Corps of Engineers also documented a sharply increasing number of sea lions foraging at the dam. That number has grown from six sea lions in 2001, to 31 in 2003, to approximately 100 sea lions annually since 2004. Until the mid-1970s, California sea lions were seldom seen anywhere on the Columbia River.

The Corps’ data only includes observations of fish taken by sea lions above water immediately below Bonneville Dam. A biometric model, based on California sea lions’ metabolic needs, indicates that 100 animals feeding in that area may consume as many as 13,000 salmon each spring. In addition, sea lions are foraging in the other 140 miles of the lower river, and in tributaries.

6) What would happen if California sea lions were allowed to continue foraging in the lower river?

Left unchecked, California sea lions could undermine the recovery of threatened and endangered salmon and steelhead runs moving through the lower Columbia River. For some stocks, recovery efforts involving reduced fishing opportunities have been under way for decades. Since the 1990s, recovery efforts have expanded to include mitigation efforts and 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.

7) What steps have been taken to deter sea lions from preying on salmon?

In the spring of 2005 and again in 2006, the Washington Department of Fish and Wildlife (WDFW), the Oregon Department of Fish and Wildlife (ODFW) and other partners made a concentrated effort to drive California sea lions away from the area below Bonneville Dam. Partners in this effort included the Columbia River Inter-Tribal Fisheries Commission, National Marine Fisheries Service (NMFS) and the U.S. Army Corps of Engineers. Despite hazing tactics that included underwater firecrackers, acoustic devices and boat hazing, the sea lions returned to the area within a short period.

8) Why can't sea lions be relocated from the Columbia River?

Previous efforts to relocate sea lions have been largely unsuccessful because sea lions frequently return to the site of capture. The experience with sea lions at the Ballard Locks in Seattle in the late 1980s is a prime example. In 1988 and 1989, resource managers captured a total of 39 California sea lions that had been foraging at the Ballard Locks and transported them to the outer Washington coast near Long Beach where they were released. Within a few weeks of the time they were released, 29 of those animals returned to the Locks to resume preying on salmon and steelhead in Shilshole Bay. The result was much the same the following year, when resource managers transported six California sea lions back to their breeding area off the coast of southern California. Three of those animals returned to Puget Sound within 45 days and a fourth was sighted in the Columbia River.

Three California sea lions that had been foraging near the Locks were captured and transferred to SeaWorld in Orlando, Fla., in 1996. Resource managers have initiated contact with accredited zoological facilities about the possibility of taking additional animals, but it is unlikely that demand will be sufficient to ease predation on protected salmon and steelhead populations on the Columbia River. A final determination on whether any California sea lions could be moved to captivity would be made by NMFS, based on the federal agency's assessment of the adequacy of captive facilities as well as the risk of possibly exposing healthy captive animals to diseases carried by wild animals.

9) What additional steps will be taken to control California sea lions on the Columbia River?

Active intervention and additional wildlife-management methods are required to restore balance between the growing number of California sea lions and endangered and threatened stocks of salmon and steelhead. The states of Washington and Oregon plan to expand hazing efforts in the spring of 2007, shifting to daily deterrence efforts as compared to last year’s four days on, four days off hazing schedule. In addition, Washington, Oregon and Idaho have petitioned the federal government for authority to use lethal means if necessary to remove individual sea lions from the vicinity of the dam, and to remove marked sea lions that have preyed on salmon near the dam. The states are applying for this removal authority under Section 120 of the Marine Mammal Protection Act.

The states’ Section 120 application is subject to a federal review process that could take several years. A congressional effort is under way to allow the states to manage the sea lion predation problem in the interim. U.S. Reps. Brian Baird, Doc Hastings and Norm Dicks of Washington, and Greg Walden of Oregon have introduced legislation in Congress that—if successful—could allow the states and four Columbia River Indian tribes to lethally removal a limited number of Columbia River sea lions as early as this spring.

10) What actions would Section 120 authority allow?

If authority is granted under Section 120 of the Marine Mammal Protection Act, state resource managers would be allowed to remove a limited number of California sea lions that have been identified as preying on salmon and steelhead in the area below Bonneville Dam. The actual number of California sea lions that might be removed would depend on various factors, but it would be less than 1 percent of the number that could be lethally removed without affecting the over-all health of the population. Lethal removal would be conducted using the most humane methods available, following the recommendations of an interagency committee that will include wildlife veterinarians. Renewed efforts to haze the sea lions away from the dam area would precede any lethal removal, and an evaluation period would follow.


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