Tim Walzworth, an assistant professor of fish ecology and fisheries management at Utah State University, told attendees that historical removal efforts have cut common carp biomass in Utah Lake but not far enough to meet program targets. He said the June Sucker Recovery Implementation Program began mechanical removals in 2009 and has removed roughly 13,000 tons—about 30,000,000 pounds—of carp since then.

"But it's always important to remember that removing carp isn't the goal of the carp removal program," Walzworth said, adding that the objective is to reduce carp effects on habitat and prey availability for the native June sucker. He presented model-based population estimates that use commercial-removal records and standardized surveys run with the Utah Division of Wildlife Resources (UDWR) and the June Sucker program to infer abundance across age classes.

According to the model, carp biomass declined strongly in the early years of the removal program through about 2017–2018 and then stabilized; biomass has crept up slowly since then. Walzworth said current estimates place biomass below the program's starting level but still above the target reduction.

Walzworth outlined several reasons the program has struggled to achieve the target. Utah Lake's large, shallow surface area creates extensive suitable habitat, making the carp population resilient to removal. Sampling gears and historic surveys preferentially catch large adults, he said, leaving a pool of smaller but reproductively mature carp that remain largely unseen by monitoring. High lake levels also create more spawning and rearing habitat and reduce the effectiveness of seines by tangling vegetation.

He described an economic challenge as well: "As biomass of carp is reduced, the catch rates we see per unit of effort...go down," Walzworth said, which raises the cost per pound removed and makes commercial fishing less profitable at low densities. He warned that the last stages of eradication are particularly costly, noting studies showing the final fraction of a population is often the hardest and most expensive to remove.

Using the population model, Walzworth ran "what-if" scenarios. He said increasing historical seining by roughly five to ten times could achieve the long-term target but that the effort required would be large—especially because catch rates decline at low biomass. He also examined alternatives, including targeted poison baits and genetic approaches such as Trojan Y chromosome strategies, and found some options may have little effect until a critical threshold is reached, after which sustained reductions could follow.

Walzworth described a new graduate-student project evaluating dynamic per-pound payments to commercial fishers to maintain harvesting effort as catch rates fall. "If there's a way we can pay for, make carp worth some money, fishermen will go out and get them," he said, noting the challenge is determining the cost and scaling needed to sustain effort.

He closed by stressing continued monitoring of the lake's ecosystem—vegetation recovery and June sucker recruitment—because the ultimate aim is ecosystem rebound, not simply removing carp. Walzworth said the team is updating models with the latest data to inform future management decisions and invited questions from the audience.