Salmon-happy Sea Lions
by Bill Monroe
So, want a better mousetrap for the sea lion problem?
Oregon and Washington have applied for federal permission to kill sea lions in trouble zones such as the one below Bonneville Dam, but no way it will happen by next spring. It is the government, after all.
And the official methods used by state and federal agents -- seal bombs, chasing and bars across fish ladders, etc. -- aren't working too well either.
Ta-da! Just in time for that special someone's Christmas stocking, federal officials are making it a bit easier for anglers to take matters into their own hands under the Marine Mammal Protection Act. The act provides for non-lethal hazing, including the limited use of firearms.
More on that in a moment.
First, though, comes an electrifying idea from a Vancouver research engineering firm.
Smith-Root Inc., is working on a proposal to target sea lions with electrical pulses it believes might keep them out of areas where salmon congest -- below Bonneville Dam, for example.
Underwater electrical force fields have been around for a long time. They've successfully blocked Asian carp and lampreys in the Great Lakes region and grass carp in Florida.
But they haven't been tested on sea lions.
The firm is developing a system that will first pinpoint a marine mammal with sonar, then zap it with electricity; or at least raise an electrical force field strong enough to keep the animal at (or, rather, out of a) bay.
Smith-Root's reasoning is sound enough.
Modern sonar systems can differentiate between mammals and fish by the quality of the return echo after a pulse of sound hits an animal's body and returns to the sensor.
Mammals are denser of bone and flesh than fish, most of which also add an air-filled swim bladder to the equation. The differentials have been proven on human bodies; why not seals and sea lions?
I especially like the proposal's pitch about the nonlethal electrical shock being not much more than that from a typical 12-volt car battery.
In fact, the National Marine Fisheries Service is also considering some tests with an electrical pulse system, according to Charlie Corrarino of the Oregon Department of Fish and Wildlife.
It's probably similar to the variable jolts on an electronic dog collar used by hunters to manage their dogs.
(I've not personally used one yet because I'd be prone to turn it up and barbecue my far-ranging German shorthair).
One might easily daydream about a future directional system carried aboard a sport boat; one that could target a nearby sea lion yet not disturb passing salmon.
Imagine sea lions entering a river where they're zapped by electricity at every turn.
Until those dreams come true, the Fisheries Service office in Seattle has good news about more proactive steps individual anglers can take.
. . . Just in time for Christmas.
Find a list on the Internet by going to: www.nwr.noaa.gov; enter "hazing," click on the "search" function, and look for a PDF file called "Potential Deterrence Methods for Pacific Harbor Seals & California Sea Lions."
Note, too, that Steller sea lions are not included. Stellers are the early arriving, very large sea lions wreaking havoc on the Columbia River's spawning sturgeon. They're protected under the Endangered Species Act and hazing is illegal.
The far more numerous, salmon-loving and brazen California sea lions target spring chinook -- usually those on the end of a fishing line and short of the net.
In fact they're getting bolder every year, nearly entering anglers' boats more than a few times in the past two seasons.
The federal list warns against using "live ammunition, bows and arrows, crossbows, spear guns, harpoons, spears, gaffs, nail-studded bats/poles/clubs, snares, concertina wire (no kidding, it's in there), poisons and guard dogs (yup; says there are "risks," including "potential disease transmission").
Feel free, though, to try underwater firecrackers, horns, bells, boats (circle only, don't butt the animal), slingshots, paintball guns and rubber bullets.
Yes, the same rubber bullets the cops carry.
Fiocchi Ammunition USA makes 12-gauge shotgun shells packed with either 00 rubber buckshot or a single rubber slug.
Noah Fishback, who works at Northwest Armory in Milwaukie, said it has to be ordered and costs $35 for a box of 25 shells.
I have no idea of the range of either load, but am reminded by Corrarino of other restrictions.
Discharge of firearms, for example, is illegal within most city limits. But not slingshots (not sure about paintball guns).
And even in a legal shooting zone, you probably wouldn't want to touch off a shot or two from a hog line without some advance negotiations with the neighbors.
Also, Corrarino said, you must be in the act of fishing and your "catch or gear needs to be threatened."
That's up for pretty broad interpretation.
I, for example, am already starting to feel threatened.
Where's that slingshot?
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