Using a spotlight and sonar display, Ely Sprenkle slowly piloted the flat-bottomed boat with odd attachments along the eastern shoreline of Tuttle Creek Lake just after dusk on Oct. 21.
The Mercury joined Sprenkle and his team for an evening of electrofishing, a practice used to search for an evaluate the growth and development of specific fish species. Sprenkle, district fisheries biologist for the Kansas Department of Wildlife, Parks and Tourism, utilizes electricity to scour the shallows for feeding fish.
The boat features two metal arms welded to both sides that swing out away from the hull. On the end of each arm is a bundle of pulse emitters, or long metal tubes that are dipped in the water. Sprenkle said the electric pulse rate and amperage can be adjusted depending on the type of fish he is seeking. For saugeye, a hybrid of walleye and sauger developed by Wildlife and Parks biologists solely for recreational fishing, Sprenkle said he uses 120 pulses per second at seven amps.
“It just stuns the fish,” Sprenkle said, adding that the fish are not harmed by the electric pulse. The discombobulated fish float to the surface and are scooped up in nets to be deposited into a reservoir in the boat.
In the fall, Sprenkle said he measures the saugeye “young of the year,” or fish that are born earlier in the year and released into Tuttle Creek Lake. Every 15 minutes, the collected fish are counted, weighed, measured and released. Sprenkle said he collected and measured 501 youth saugeye per hour on Oct. 21. He said 2021 “is by far our best year” for the survival of young fish of that species. The second-best year was 2017, when Sprenkle said he collected 370 saugeye per hour.
“Electrofishing is used to evaluate how big the spawn was,” Sprenkle said. “Saugeye is stocked, so we use that method to measure how successfully the fish grow up.”
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Fisheries aide Billy Coleman started working for Wildlife and Parks in May, and he said he’s loved fishing since he was a child. He said one reason for keeping track of saugeye health data through electrofishing is because saugeye share a taste for shad, a specific type of fish, with other aquatic species.
“If we stock saugeye and have a good shad spawn, then conditions will favor the saugeye,” Coleman said, “but they aren’t the only fish (in Tuttle Creek Lake) that eat shad, so that’s why we have all these sampling methods to collect data for all the different species of fish we keep track of.”
Sprenkle said saugeye is one of the more popular fish varieties in both Tuttle Creek Lake and Milford Lake. Saugeye was created when biologists took the eggs from a female walleye and fertilized them with the preserved sperm from a male sauger. Sprenkle said Wildlife and Parks scientists will capture female walleye at El Dorado Lake, harvest their eggs, release the fish and drive the eggs back to the Milford Fish Hatchery.
“We’ll fertilize the female eggs with male sperm right there in the controlled hatchery system,” Sprenkle said, “and once they’re fertilized, they’re raised up in the hatchery.”
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Sprenkle said this season’s class of saugeye “young of the year” appear mostly healthy, with an average length of 9 inches. He said the historical average length for young saugeye has been 7 inches. He said there is a catch limit of 21 inches for walleye and saugeye at Milford Lake, which differs from the rules at Tuttle.
“Saugeye in Tuttle get flushed out every few years, so we only have a 15-inch length limit there,” Sprenkle said. He said Tuttle Creek Lake is “more of a flow-through” system due to the nature of the lake’s design, and therefore has higher release rates than Milford. Sauger — which is a cousin fish to the walleye — tolerates muddier waters better, but Sprenkle said they don’t grow as big.
“We produce those (saugeye) for our anglers, but since they’re a hybrid, they’re not reproducing on their own,” Sprenkle said, “so I have to stock them every year to maintain the numbers.”
Sprenkle said Tuttle was stocked with two million saugeye “fry,” or newborns, this year. Biologists also stocked about 50,000 “fingerlings,” or fish that’ve grown to at least an inch and a half in length before being released. Wildlife and Parks officials operate four hatcheries across the state, including Milford, and the entire system produces about 39.5 million fry and 3.5 million fingerlings for Kansas public waters annually.
Sprenkle said saugeye are a “neat fish” that have features similar to walleye but have “more dynamic color patterns.”
“They have an eye that reflects like a cat,” Sprenkle said. “You can find them with a spotlight. They tend to be a bit more aggressive. … They put up a good fight and are great table fare.”
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