A Vancouver, Wash., company has developed a new system using what it says are non-lethal electrical pulses designed to keep sea lions off public marina facilities and Port of Grays Harbor officials are considering how it might be employed locally.
Using what is said to be non-harmful levels of direct current, the Smith-Root company believes the system can help solve one of the most vexing problems at the Port’s Westport marina as well as most saltwater marinas in the Pacific Northwest.
It also has been proposed to the Port of Astoria, among others, as a way to control sea lions in the Columbia River and other ports.
Carl Burger, Smith-Root’s senior scientist, told Port of Grays Harbor officials that a similar system is in use in Geneva, Switzerland, to keep fish away from electrical turbines. The company also has done a demonstration for the Bonneville Power Administration.
“There are different types of applications for culverts or screens, pump intakes and hydropower turbines,” he said of the technology for deterring fish.
The electrodes can even be set up in a circle around a construction area to keep fish out, according to the company.
Based on preliminary tests on Pacific harbor seals at the Vancouver, B.C., Aquarium, Smith-Root conducted additional research on California sea lions in 2008 with marine mammal scientists at Moss Landing Marine Labs. Using a mild, non-lethal field of pulsed direct current, tests were designed to assess the voltage gradient levels that sea lions could detect, and then to assess deterrence reactions with and without food present, the company said in a statement about the tests.
Burger assured Port commissioners in a recent video demonstration that there was no danger of getting electrocuted from the charges, which he said are about 8 volts. He said tests have shown that humans don’t even feel the electric pulses.
‘It’s much like a bird landing on a high-tension wire,” he said. “They don’t feel a thing and they become part of the field. … These animals are very, very sensitive to a mild field.”
Boats can go right through the live electric field and the occupants feel nothing, and humans rarely can detect the charge, even though it is enough to ward off sea lions and seals.
After watching a video demonstration on the technique at the Port, Westport Mayor Michael Bruce called it “very electrifying.”
Westport has considered a resolution supporting signs that encourage people not to feed the sea lions, he said.
Port Executive Director Gary Nelson said the problem has gotten so bad that a net-pen salmon raising project has nearly been abandoned and the Port has had damage to a number of its facilities caused by the sea lions.
“It’s encouraging to see that someone is making some progress with some deterrence that appears to be safe and sane,” he said.
One of the videos shown by Burger was at a new $1.1 million visitor’s dock at the harbor in Moss Landing, Calif.
“Within a week, it was colonized by sea lions – hundreds of animals two and three deep, virtually every hour of every day,” he said.
The company worked with the National Oceanic and Atmospheric Association, and it notes that under the Marine Mammal Protection Act, local harbormasters have the ability to use deterrence, particularly electrical deterrence technologies, “in defense and protection of property,” Burger told the Port.
“The first thing everyone wants to know is if we can do this without hurting the animals and the second thing is about permitting,” Burger said.
During the Moss Landing tests, the company wired two of four of the docks on a new visitors pier and then quickly cleared them of sea lions by simply turning on the low-level electrical current. The docks cleared in about 25 seconds, and when a few of the sea lions tried to climb back up, they just as quickly jumped back into the water when encountering the current.
“We have over 1,100 video recorded observations of animals trying to repopulate, and not a single one would stay on for more than about six seconds,” Burger said. “They sniff it, and they don’t know what it is. But they know that they don’t like it. It’s an irritant.”
Burger believes it’s possible to use the system 24 hours a day without a problem or any effect to people.
“That is an issue,” Burger said. “They are going to go someplace, so the answer may be to build them a smaller platform out in the middle of the harbor and turn it over to them. They are going to someplace else. If we don’t want them on our dock, then we either have to find another place to go or give them another place to go.”
The one big issue is where the sea lions go after they have been deterred by the electrodes.
Burger said the company currently has some patents in the works before it begins commercial application of the process.
“The word is slowly getting out,” he said. “We believe we have a way to not only protect docks but to maybe come up with smaller pads for boat platforms. That way when boat operators come into port, they can go plug this thing in, go have lunch and then come back without having animals crawling all over their boats.”
The company also hopes to interest the U.S. Navy.
Unlike other methods, such as sound or rubber bullets, Burger said the sea lions never get acclimated to the electrical pulses.
“After two weeks, we saw animals clearly avoiding those middle two segments, even when they were unenergized,” Burger said.
Westport Marina Manager Robin Leraas said she was impressed by the demonstration but the biggest question she has is how much the system would cost and whether it work on a large-scale facility like the marina.
“It could possibly be a good solution, I just don’t know the feasibility of cost,” Leraas said.
The problems caused by sea lions, she said, has gotten so bad that they have damaged electrical hookups at the marina, and have forced early release of net-pen fish at float 4.
“It’s just an ongoing issue and we’re just trying to nip it in the bud before it gets really bad,” Leraas said.
In a follow-up interview, Burger said the company is making a presentation to California harbormasters in the fall.
“Essentially, the technology is ready, but we’re a small business of 45 people, all employee-owned,” he noted, adding that the specifics on cost and ability to do a project depend on the size of the dock, the depth and width of the water or the dock to be protected.
“But if an order came in, we would build to address the unique needs of the project,” Burger said. “That’s how we operate. We come up with the engineering design and the plans and get the client to approve those. If they want the technology, we will build to suit.”