Of all the things that affect the population of walleyes in South Dakota lakes — water levels and quality, abundance of bait fish, and pressure by anglers — the last element is the one that fisheries managers can control most.
Regulating anglers to protect fish populations is the driving force behind the bag and size limits placed upon anglers by the South Dakota Game, Fish & Parks Department. It's also the reason that size limits, slot sizes and bag limits can change from year to year and lake to lake.
For that reason, it's incumbent upon state anglers to know the rules for the lake they're fishing on, and to also always carry a tape measure or ruler so they don't needlessly break the laws.
This year, the big change for walleyes came on Lake Oahe on the Missouri River north of Pierre where anglers can take many more smaller fish than normal.
Walleye bag limits have stayed fairly steady statewide at a daily limit of four fish and a possession limit of eight fish, with one per day over 20 inches. West River walleye lakes have special rules, such as a 15-inch minimum at Angostura and Shadehill reservoirs; and a slot size at Orman Dam on the Belle Fourche Reservoir where fish can only be kept if they are under 15 inches or over 18 inches, with only one over 18.
But on Oahe, anglers this year can take eight fish a day (with four under 15 inches) and possess up to 24 at a time due to a unique situation on the Missouri River, said John Lott, state fisheries administrator.
Lott said the bag and possession limits on the smaller walleyes was raised on Oahe due to a shortage in their favorite bait fish, the rainbow smelt. "We've got a lot of small walleyes, they are low on food resources out there for them, and as a result they won't grow very much," Lott said.
So that forced a decision: let those small, slow-growing walleyes linger about and be lost to predators and disease; or let hungry anglers take more of those fish.
"We're just viewing this as an opportunity for anglers to harvest additional fish at a time when that is not going to hurt the population," Lott said.
A similar situation came about in 2001, Lott said, when the daily walleye limit on Oahe was raised to 14 after there was an abundance of small walleyes and a lack of bait fish due to water releases that flushed away smelt down the Missouri River dams.
In general, he said, slot sizes and bag limits for any species of game fish are designed to accomplish what fishery managers seek most — to create a consistent, high-quality fishery that provides anglers a good opportunity to catch fish and occasionally land a lunker. "Our objective is to keep quality fisheries year in, and year out," Lott said.
While some anglers complain about the rules (most of which are posted on signs outside boat launches and in the state fishing handbook), most accept that the regulations protect the long-term viability of fish populations, according to Mike Cummings, owner of The Rooster sporting goods store in Rapid City.
"There's more fishing pressure, and to maintain a fishery without it getting fished out, I think they have to do that," Cummings said of the regulations. "It's probably the only way a lake can survive and maintain itself."
Cummings said most anglers know the rules — "it's their job to know" — and follow them.
Especially at a closed site like the Belle Fourche Reservoir, he said it's important to set limits.
"It is what it is; they don't like it, but at the same time they would basically fish the lake out, and there wouldn't be anything left," he said.
While Lott may be somewhat biased and proud, since he is the top fisheries manager in the state, he said South Dakota waters are flush with walleyes now and that state anglers should feel lucky. "We're spoiled, I would say," he said. "Non-residents who fish here are more satisfied with their trips than the residents, because we have it so good."