WORTHINGTON — Twenty carp captured a month ago from Lake Okabena are now swimming around with radio transmitters surgically implanted in them.
The work was completed by Wenck Associates, a Twin Cities-based engineering firm that specializes in hydrology, flooding and water quality. This is the second time the Okabena-Ocheda Watershed District has funded a project to surgically implant radio transmitters in carp.
By tracking their individualized signals, the watershed will be able to learn where the roughfish congregate in hopes of doing a wintertime seining on the lake. A larger than acceptable number of carp in the lake is contributing to higher levels of suspended sediment and lower levels of aquatic vegetation. As a result, water quality and clarity in the lake isn’t as good as it can be.
Watershed administrator Dan Livdahl will track the carp through the fall and winter. He reported to watershed managers Tuesday that he found all 20 carp a week after they were surgically implanted with devices. The new implants emit a stronger signal than those implanted in 15 carp in May 2019, and Livdahl anticipates he will be able to find the fish easier under the ice this winter.
The watershed district approved funding earlier this summer to do the second round of surgical implants because only 13 of the original radio transmitters were emitting signals. Some of those carp hadn’t moved in months, leading Livdahl to suspect they were dead.
The carp with the new implants were recently tracked to a deeper area of the lake along the lake’s west side, Livdahl reported Tuesday.
“It’s about 10 feet deep there, and all 20 were there,” Livdahl said.
He also reported that Wenck continues to work on a separate proposal looking at barriers or ways to trap carp in addition to seining.
In other business, the board:
Received an update on the progress of the Lake Ocheda drawdown. Livdahl reported that no water was flowing over the dam on the south side of the west basin as of Monday morning, but that changed with the rain and snow showers Monday and Tuesday.
Livdahl reported that Randy Erwin trapped seven beavers from the Ocheyedan River between the dam and 310th Street, and there haven’t been any more beavers trying to construct dams in that area for the past three weeks.
Board Chairman Rolf Mahlberg reported that carp have been seen pooling in some of the shallow areas of the basins, and Livdahl noted what appeared to be dead carp in the basin at Sportsman’s Park on Monday.
“We may already have a bit of a kill going, based on warm temperatures and low water levels,” Livdahl said.
“It looks good on our basin,” noted Paul Langseth, an advisory board member, of the lake’s east basin. “The water is really shallow for a long ways. I’m hoping we get a good (fish) kill on it.”
Discussed briefly the 2021 budget. Mahlberg agreed to coordinate the performance evaluation of Livdahl as watershed district administrator.
Also, Livdahl said other large budgetary items for the year could include carp removal from Lake Okabena and a clean water project on the ISD 518 property along Crailsheim Road. Since both the city of Worthington and the E.O. Olson Trust have set money aside for the removal of carp, the financial impact to the watershed district is yet unknown.
Received an update on the fish barrier installation on the Minnesota West storm water pond. Jeff Meinders fabricated and installed a grate to cover the outlet that leads to Lake Okabena. The work was completed Oct. 23, and the total project cost was just under $5,000. Livdahl said the custom-built aluminum screens can be removed for cleaning as needed.
Learned that Livdahl, along with watershed managers Mahlberg and Casey Ingenthron, evaluated the forebay on the district’s W-9 project along Nobles County 25 northwest of Worthington. Last cleaned out a decade ago, the sediment-holding ponds were mostly dry this fall. Following their assessment, a contractor was hired to remove sediment from the water holding ponds. The cleanout was completed Oct. 30 and cost the district $5,625, Livdahl reported.
Approved a shoreline work permit for Todd Heironimus, Worthington, to install fieldstone riprap and remove some concrete chunks from his property on Lake Okabena; and an erosion and sediment control permit for V&O Properties during construction of a duplex along Flower Lane, near South Shore Drive.
Assigned Ingenthron to be a voting delegate during the Minnesota Association of Watershed District’s virtual conference in early December.