Winterkill won't affect fishing in Southwest ND, Game and Fish officials say
Subzero colds, glacial northern winds and near-record snowfall this winter had a chilling effect on residents across the state, but The North Dakota Game and Fish Department is saying that our gill-bearing aquatic neighbors, fish, suffered greatly—but not nearly as bad as initially projected.
"What really affects fish populations is winterkill, or in other words, whenever snow covers the surface of the ice and blocks the sunlight," Jeff Hendrickson, district fisheries supervisor with North Dakota Game and Fish, said. "We have some lakes and ponds that winterkill almost every year like Beach and Belfield ponds, but sometimes we have other bodies of water, like larger lakes, that winterkill too. That's where it becomes a bit more concerning."
Winterkill is a term used to describe the loss of fish during the winter months as oxygen levels become depleted in bodies of water. Submerged vegetation and algae are primary sources of oxygen through the process of photosynthesis, and this process can become greatly reduced as ice and snow on lakes and rivers limit sunlight from reaching the plants.
"Larson Lake near Regent and Dickinson Dike in Dickinson both winterkilled this year, which doesn't typically happen," Hendrickson said. "We suspected early on that Patterson Lake might winterkill based on the amount of snow coverage we were seeing, but it didn't and came through pretty good. There have already been a lot of rumors circulating about Patterson Lake and that simply isn't the case, the stock there is fine."
Anglers are expected, according to Game and Fish staff, to experience no discernible change this spring and summer on southwestern North Dakota lakes and rivers—despite rumors spurred by social media that this year's winterkill had severely affected fish populations.
"We already supplied perch and catfish in Belfield pond, catfish in Dickinson Dike, with plans to put bass and bluegill in the near future; and in Larson Lake, we already stocked with perch up to 10 inches in length. Despite the winterkill, those places already have fish in them now," Hendrickson said. "Anglers won't miss a beat, they'll be able to catch fish there all summer."
Hendrickson did say that should anyone observe dead or struggling fish, they should immediately report those findings to their local Game and Fish Department office. By sharing this information, which includes species and approximate numbers and sizes of each kind of fish, staff can identify which bodies of water are experiencing winterkill and to what extent and move forward on restocking.
"A few fish die almost every year in lakes across North Dakota; we aren't looking for reports about one or two fish found on the shoreline. What we are looking for are banks near water that are filled with dead fish," Hendrickson said. "If you see a bunch of dead fish, we'll go out and check it out."