Doug Leier: NDGF continues to experiment with fish stocking
I’ll interrupt the usual “migration” of hunting information this time of year with an interesting update on the future of fishing in North Dakota where fisheries biologists continue to mix the standard tried and true fish stocking with innovation and experimentation.
North Dakota Game and Fish Department fisheries biologists have for years stocked millions of walleye fingerlings across the state each June. Last year, 12 million walleye fingerlings were stocked in a record 180 waters .
In addition, Jerry Weigel, Department fisheries production and development supervisor, estimated 170,000 advanced walleye fingerlings stocked in North Dakota waters in 2020. These bigger fish, longer than those stocked in June, are hopefully less interesting to predators.
“We’ve been experimenting by growing some of our traditional 1 ¼ - to 1 ½-inch fish for an extra six weeks up to, say, 3 to 4 inches to see if we can have a little better success in lakes with high bullhead or perch populations,” Weigel said. “Our hope is that these larger, advanced fingerlings get passed on by predators and we can create a little better walleye fishery in some of these lakes.
“The big thing about the advanced fingerlings is that most are of a size where they’re too big for the bullheads to eat,” he added. “They get to a size that the bullheads don’t even attempt to eat them.”
Even so, survival for the advanced fingerlings isn’t certain because even bigger fish, like adult walleye and northern pike, remain a threat.
As with most science and fisheries management experiments, the initial results don’t necessarily predicate the final assessment.
“Up in the Turtle Mountains, there are a handful of lakes, Lake Metigoshe included, that we’ve been stocking for a while now that have shown some early signs that it’s looking like these advanced walleye fingerlings are positively contributing,” Weigel said.
The advanced fingerlings stocked this year in about mid-August in a number of waters from Braun Lake in Logan County to Upsilon Lake in the Turtle Mountains, were raised at Garrison Dam National Fish Hatchery near Riverdale.
Here’s how it works according to Weigel: “We re-pond them in the end of June and we don’t feed them minnows or anything … they literally just eat natural food in the ponds, and we get amazing survival and outstanding production. We do this on a limited basis because it creates a lot of pounds of fish and dramatically fewer fish than our traditional smaller walleye fingerlings.”
Yet, the impact on the hatchery is minimal, while the goal of improving the recruitment of walleye young at problem lakes is certainly attainable.
It will take time for the advanced walleye fingerlings to grow big enough to be of any interest to anglers.
Leier is a biologist with the Game and Fish Department. His email is email@example.com