Electrofishing targets carp for tagging and removal from Lake Okabena
Boaters should avoid the box nets, and fishers in particular should avoid casting nearby, because those types of nets “collect” lures.
WORTHINGTON — A strange-looking boat with two wiry contraptions dangling from its prow will be patrolling the waters of Lake Okabena for the next few days, and fellow boaters should give it some space for its electrofishing mission.
The Okabena-Ocheda Watershed District's Board of Managers hired Carp Solutions, a University of Minnesota start-up company, in an effort to both determine how many carp live in Lake Okabena, and then offer some potential solutions for decreasing that number.
William Wright, fisheries specialist, and Charles Egberg, project assistant, will crew the electrofishing boat through Wednesday, zapping carp, netting them, measuring them, chipping them and then putting them back into the lake.
“We’re excited to be working on more lakes in Minnesota. We’re happy to help with the carp removal process,” Egberg said Tuesday, prior to heading back onto the lake.
“We’re hoping to make a big impact, and hopefully this can start a healthy chain reaction with the lake,” Wright added.
The process is simple. The two men take turns piloting the boat and standing on its raised deck area, where they lean on its railings to watch the water below, armed with rubber gloves and a net. Two poles stretch out ahead of the boat, and from each dangles a metal piece dubbed a “spider,” with six flexible prongs that fan out and resemble insectoid legs.
Those "spiders" pump a 25 to 30 amp electric charge into the water to momentarily stun a fish so that it can be scooped into the boat and given a tracking tag before being released back into the lake.
On Monday, the two men caught 41 carp, and by the end of the day Wednesday they hoped to catch and tag a minimum of 100 and a maximum of 200.
That’s not the end of the process, though. They will also be setting up four box nets on the lake, which will be marked by poles and safety signs so that boaters can keep away from those, too. The box nets are designed so that when triggered by a human on the shore nearby, four nets that were resting on the bottom of the lake rise up to capture the fish between them — which can then be easily removed from the lake.
The box nets will be baited with cracked corn, a foodstuff beloved by carp and no other residents of the lake, and then, observers will watch the trackers to find out when the carp like to visit the nets.
That will tell them the best time to spring the box net traps, catch the carp and remove them from the lake.
Boaters should avoid the box nets, and fishers, in particular, should avoid casting nearby, because those types of nets “collect” lures.
Carp are an invasive species that root around the bottom of the lake in order to feed, digging up plants and killing them while increasing the amount of sediment in the water, which in turn increases the number of nutrients in the water. That can lead to smelly algae blooms, some of which can even be toxic.
Wright and Egberg warned that if their efforts to eliminate carp from the lake work, people will see a return of lake weeds and vegetation, which are currently fairly sparse in Lake Okabena. While swimmers and boaters don’t necessarily like the plants, their return would be a positive sign for the lake’s ecosystem.
“It’s kind of a passion project for a lot of us,” said Wright, noting that almost everyone on the Carp Solutions team is from Minnesota, and the only one who isn’t, hails from Wisconsin.
“We all care about the environment, and we all want to help restore things,” Egberg said.