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Updated January 2013
Off and on for the past several years, ODFW has been hazing California sea lions at Willamette Falls to protect two listed stocks of native fish – the wild upper Willamette River spring chinook salmon and upper Willamette River steelhead. Both are listed as threatened under the federal Endangered Species Act and predation of listed salmon and steelhead by California sea lions below Willamette Falls has been identified as a concern in the Upper Willamette River Salmon and Steelhead Recovery Plan.
The Oregon Legislature in 2011 passed a law (HB3255) directing ODFW to haze sea lions at Willamette Falls seven days a week from February through April. The hazing will take place during daylight hours from Feb. 4 through April 30, 2013 from Willamette Falls downstream approximately one mile to the Abernathy I-205 Bridge. This time period coincides with the migration period of spring salmon and the largest concentrations of salmon/steelhead and sea lions. The fish are most susceptible to predation in this stretch of the river because Willamette Falls poses a barrier to upstream migration. As a result, the fish congregate in the pool directly below the falls while they prepare to enter the fish ladders that allow them to move upstream to their spawning grounds. The fish essentially become trapped against the falls, and this lack of escapement options makes them easy targets for sea lions.
California sea lions are managed under the federal Marine Mammal Protection Act (MMPA) of 1972. The MMPA prohibits the killing or harassment of marine mammals in U.S. waters. Only under very specific circumstances and certain procedures can authorization be obtained to lethally remove sea lions. At this point ODFW is not pursuing such authorization. However, ODFW has obtained a Letter of Authorization from National Marine Fisheries Service (NMFS) for non-lethal hazing of Willamette River sea lions, to see if this approach is effective in reducing predation on listed salmon and steelhead. This will be the second full season of sea lion hazing on the Willamette. The first year of the program was four weeks in 2010. A full three-month program took place in 2011. The program did not operate in 2012 due to budget constraints.
There are currently no plans to seek federal authorization for a lethal take permit on the Willamette. ODFW prefers a non-lethal approach before pursuing other options. ODFW does have a limited lethal take permit for sea lions on the Columbia River. However, obtaining that authorization on the Columbia took years and was subject to litigation. The Willamette is a smaller river, with fewer fish and fewer sea lions, and there is some evidence hazing is effective at reducing losses of listed fish to sea lion predation.
Portland State University students observed sea lions at Willamette Falls from 1995 through 2003 and observed from 4 to 10 different sea lions working in that area. They observed 296 spring chinook predations and 243 steelhead predations, estimating a total of 2,133 salmon/steelhead predations during the observed period. Biometric modeling, based on California sea lions’ metabolic needs, indicates that sea lions may eat as many as 1,300 salmon each spring. On the Columbia River, some estimates of the total predation rate suggest it could be as high as 16-20 percent of the total run. In 2011 and 2012, observers documented as many as 18 and 21 California sea lions, respectively, in the hazing area below Willamette Falls. Biologists estimate these animals consume 4-7 salmon/steelhead a day.
We are seeing some signs that the hazing program is working, however, it’s really too soon to say if predation will be curtailed due to our efforts. ODFW only has two prior seasons experience hazing sea lions at Willamette Falls. ODFW sea lion hazing crews have been successful in moving sea lions away from the falls where migrating salmon and steelhead congregate. We also know that when hazing stops the sea lions return to the falls to prey on salmon and steelhead.
ODFW has been directed by the Oregon Legislature to continue the hazing program through April 30, 2013. There are no plans to continue the program beyond that time. However, because protecting the salmon and steelhead is critical, we believe it’s important to continue the hazing and hopefully will work a way so we can maintain a hazing presence at the falls.
HB 3255 authorizes ODFW to spend $112,932 for the 2013 sea lion hazing program. Those funds are provided from revenue generated by the sale of hunting and fishing licenses. No general tax dollars are used to fund this program.
Seven ODFW employees are employed directly by the sea lion hazing program. In addition, the program is supported by an experienced fish biologist and other staff members as a part of their regular duties.
Safety is paramount. The area where the hazing takes place is very dangerous whether hazing from the water or land. All crew members are trained in CPR and boating safety. They also are trained in the safe use of firearms and explosive acoustical devices that are used in the sea lion hazing program.
Hazing crews use “cracker shells” – essentially firecrackers that are shot out above the water from a 12- gauge shotgun. Cracker shells explode near the surface of water and make a loud “bang” that typically scares the sea lions out of the area. Crew members also use “seal bombs” – small waterproof pyrotechnic devices that are designed to go off underwater. Three crew members work from an 18-foot aluminum boat. One person operates the boat and looks for sea lions, a second person uses the shotgun, and the third person deploys the seal bombs. A fourth crew member is stationed on a catwalk above the fish ladders at Willamette Falls and operates a handheld radio and shotgun armed with cracker shells. The hazing crew members are always equipped with eye and ear protection, rain gear, and data sheets noting the location of sea lions, predation, and other information.
ODFW has been hazing sea lions for a number of years and there doesn’t appear to be any harm to the animals as a result of the hazing activities. The primary purpose of hazing is to get the sea lions to leave the falls area and move down river.
ODFW is very sensitive to the concerns that surrounding neighborhoods have regarding the noise generated by the hazing program. People in the surrounding areas will hear loud “bangs” that sound like fireworks. These noises will be intermittent throughout the day and muffled in some cases by the sound of Willamette Falls, the Willamette River, and traffic along the I-205 freeway. Because hazing is taking place during daylight hours, we hope that the noises will be muffled by the normal traffic and work activities in that area. We also hope the sea lions will learn they are unwelcome around the falls, reducing the need for the use of pyrotechnics to drive them downstream.
California sea lions are found all along the west coast of 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. 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. The California sea lion population has grown from about 10,000 animals to about 300,000 today.
- There are many sources of risk to wild salmon and steelhead in the Willamette River and its tributaries. Some of those risks have been addressed that have and are being addressed by federal, state, tribal and local governments. For example:
- Millions of dollars have been spent restoring spawning habitat
- Millions more have been spent to make hydroelectric dams more “fish friendly”
- Fisheries have been reduced substantially
- Hatchery programs have been modified to reduce the impact of hatchery fish on wild populations
Sea lion predation is a relatively new and major risk that needs to be addressed.
ODFW has information about California sea lion control on its website.
Under the Marine Mammal Protection Act, regulatory authority over sea lions rests exclusively with the federal agency, NOAA Fisheries. NOAA Fisheries’ Northwest Regional Office has posted a website that answers many of the questions anglers may have about protecting themselves from aggressive sea lions while fishing. ODFW encourages anglers to visit NOAA Fisheries’ Deterring Problem Seals & Sea Lion page.
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