Back At Bonneville and Hungrier Than Ever
A Steller Sea Lion. Photo from NOAA
The all you can eat seafood buffet at Bonneville Dam is open for business.
Early season numbers from Oregon Fish and Wildlife tell us that anywhere from a dozen to two dozen sea lions are hanging out at the dam, enjoying the easy pickings of salmon and sturgeon. Most of are Steller sea lions, only a few of them are of the California variety.
Those numbers are typical for late February, according Rick Hargrave of ODFW. Steller sea lions arrive first. The number of California sea lions will pick up starting in March.
What is unusual – is how much fish they’re eating.
Hargrave says that as of last count, the stellers ate 531 sturgeon, almost twice as many as they ate by this time a year ago. It’s an amount that Hargrave calls, “significant”. In all of 2009, the stellers took about 1700 sturgeon at Bonneville.
Those numbers only include what wildlife officials have been able to observe at the dam. Hargrave says the stellers also feed further downstream, as far west as Beacon Rock. At that location they’re too far away to be observed and are eating an uncounted number of sturgeon.
Of particular concern to officials, the stellers appear to be going after large breeding females, the ones with eggs for future generations of fish.
Hazing of the sea lions at Bonneville began in January. But beyond that, Hargrave says they have few options for controlling steller predation at the dam. The stellers are listed as a threatened species, trapping or killing them is against the law. On the other hand, sturgeon are not listed so they don’t have nearly as much legal protection.
It’s the opposite of the situation between California sea lions and salmon. In this case, the fish are endangered but the sea lions are not. That’s why the federal government is allowing wildlife officials to trap, remove or euthanize some of the California sea lions at Bonneville.
Sturgeon Numbers Are Down
Data provided to fishery managers in Oregon and Washington show that the number of sturgeon in the Columbia River has declined since 2005. While looking relatively steady through 2007, there was a 28% drop off by 2008.
As a result, Oregon and Washington dramatically cut back the sturgeon season that begins March 1. The catch limit for 2010 is set at 24,000 sturgeon below Bonneville Dam. That’s down 40% from 2009. Hargrave says, “predation by stellars is compontent of that.”
California Sea Lion Trapping Returns
As for the California sea lions, Hargrave says the trapping season begins the first week of March. The controversy surrounding this program may only grow. Not a single zoo or aquarium has agreed to take in a sea lion this year. So when wildlife officials capture a California sea lion who’s on the list of heavy predators, it will be euthanized. Sea lions that are not on the list are branded, tagged and then released.
In 2009, 20 California sea lions were trapped at Bonneville. Of those, six were released, four were sent to zoos and aquariums, and ten were put down.
Stellars have been eating salmon and sturgeon there always. The salmon and sturgeon have always been plentiful. What has changed? Commercial overfishing, and tourist and private overfishing have raped the waters, but the animals get blamed and are put to death. Even the endangered Stellars. The killing season is set to begin…
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