Fish survey yields encouraging results on North Dakota's Wood Lake after August die-off
The results of the Oct. 3 electrofishing survey are particularly encouraging for walleyes, which were among the hardest-hit species in the August die-off.
BENSON COUNTY, N.D. – Fish populations in Wood Lake are holding up quite well, after an August blue-green algae bloom depleted oxygen levels and killed hundreds of fish, a North Dakota fisheries manager says.
Randy Hiltner, Northeast District fisheries supervisor for the North Dakota Game and Fish Department in Devils Lake, said an electrofishing survey conducted Monday, Oct. 3, produced a variety of fish species, including yellow perch, walleyes, bluegills, largemouth bass, northern pike, pure muskie and white sucker.
“We were pleasantly surprised,” Hiltner said. “Walleye of all sizes were very numerous in our electrofishing survey, from 6 inches up to 24 inches, and a lot in that 15-inch range.”
Located in Benson County south of Devils Lake, Wood Lake covers 103.6 acres. Bass, pike and panfish produce naturally, while the walleye population is reliant on stocking. Since 2015, the Game and Fish Department has been stocking pure-strain muskies into Wood Lake, as well.
The results of the electrofishing survey are particularly encouraging for walleyes, which were among the hardest-hit species in the August die-off, Hiltner said. Dead walleyes up to 29 inches washed up on shore, while perch and other species were gulping at the surface, Hiltner said. The water took on a grayish color, and even crayfish showed signs of stress, he said.
Dissolved oxygen measurements returned to more favorable levels a few days later.
“It was bad, but a portion of the (fish) population obviously made it through this,” Hiltner said. “There must have been a lot of walleyes to start with, because it’s not that big of a lake. We counted those dead walleyes but there were lots left, as well.”
During the recent electrofishing survey, Hiltner says, the crew sampled largemouth bass from 4 inches up to 18 inches, bluegills from 2 inches to 8 inches, very small perch up to 8 inches and pike from 24 up to about 36 inches, in addition to walleyes up to 24 inches.
On the downside, he said, the number of 7- and 8-inch bluegills – nicer fish by bluegill standards – along with bigger largemouth bass seemed to be less abundant during the recent electrofishing survey.
Considering the number of dead fish washed up on shore in August, though, the outcome could have been much worse.
“The overall sample went pretty well,” Hiltner said. “There are lots of fish left in there.”