No walleye yet

This summer will mark three years since Ballville Dam was removed from the Sandusky River near Fremont, and so far no spawning walleye or white bass have been found above the former obstacle. Ohio Department of Natural Resources officials at the time said it would take "a few years" for fish to make their way upstream during their annual spring spawning migrations, but they didn't know how long the natural process would take. Since 2019, ODNR has been conducting post-dam removal studies to determine changes in fish populations. Eric Weimer, fisheries biologist supervisor at ODNR's Sandusky Fisheries Research Unit, said ODNR provided grant funding for studies to be conducted by two graduate students at the University of Toledo for the last two years. He said Taylor Sasak is looking at the fish community and looking at changes above where the dam was compared to conditions below the dam. "She goes out pretty much every week during the spring walleye and white bass run," he said. Although the main obstacle for fish to move upstream has been removed, no walleye or white bass were found last spring or so far this spring during the spawning migration between for former dam site at Ballville and the first dam near Tiffin, Weimer said. "However, I know she's found a couple of other species," he said. "There was a juvenile white bass upstream last summer and juvenile flathead catfish. We know that there are flatheads below the dam, but none had been seen above the dam." Studies in spring 2020 were cut back considerably by the pandemic, but have resumed this spring. "In the past there has not been a ton of work done upstream of the dam," Weimer said. "We know that there's good spawning habitat upstream of Ballville." That information comes from a study conducted 10 years ago, before the dam was removed, to document the state of the river at that time. Also, a walleye-spawning study was done in the 1990s that showed walleye would spawn in that section of the river. Weimer said another student — Madison Myers — is mapping the areas of habitat between Tiffin and Fremont. "This many acres of one kind of habitat and that many acres of another," he said. The information will be used to determine how many walleye and other species could be supported. He said Myers is looking at other impediment to fish movement. Even though the dam has been removed, he said there are natural blockages and obstacles. "There's a reason they put the Ballville Dam where it was," he said. "The bedrock shelf at high flow might be an impediment to fish moving upstream." In addition, Weimer said a weekly creel study is done each year at Fremont — with the exception of last spring — where data is collected on fish age and growth. Anglers are interviewed and data is compared to the length of fish being caught by anglers. Fish population studies Although she hasn't found any walleye yet upstream from the former Ballville Dam, Taylor Sasek said she's been testing on a regular basis through an ODNR grant "to develop a habitat suitability index model for spawning walleye on the Sandusky River in order to assess the quality and quantity in the river from Sandusky Bay to the first lowhead dam." Twice each week, Sasak and an ODNR biologist take samples downstream of the former dam site and upstream near Wolf Creek. "Right now the walleye are spawning," Sasek said. "I am assessing the abundance of walleye that are coming into the river to spawn. It's known historically that they spawn downstream. We're checking to see if they are using the newly available spawning habitat upstream." She said no walleye have been captured yet during her survey work. "Basically, I'm in a boat electrofishing," she said. She floats down the river for 5 minutes at a time, shocks the fish using a system which sends electrical current through the water, and then collects any walleye she finds. "As soon as the white bass run starts, I'll be collecting them too," she said. That's coming up in mid-April. "They overlap," she said. "White bass typically spawn after walleye." Although Sasak said there have been no walleye found so far between Fremont and Tiffin, she said upstream spawning habitat is of good quality - potentially better than downstream habitat. However, walleye and white bass have an instinct to return the place they were hatched to lay their eggs for a new generation. They usually don't change location unless something happens that forces them to move. "Walleye and white bass both exhibit a homing behavior," Sasek said. "Hopefully, we'll have an overall increase the walleye population and white bass population over time." Downstream from Ballville so far this year, Sasak said she's found a larger number of walleye than she did in 2020 surveys. "Last year's walleye run was fairly weak in my opinion," she said. "2021 seems to be stronger." In addition to looking for walleye and white bass, Sasak conducts other studies to look at the residential fish community in the river - upstream and downstream. The study is a post-dam removal follow-up to similar studies done before the dam was removed. Last year, she conducted fish surveys July through September at sites above and below the former dam. She said she used similar methods that were used during a pre-removal study conducted in 2009 by ODNR and Ohio EPA, she said. To survey fish, Sasak said she uses "tote barge electrofishing," in which she zig-zags across the river from one bank to another. "Then I capture all the species of fish," she said. Preliminarily, Sasak said she has found different fish communities in the river above and below the site of the former dam. "There are differences in composition and species of fish in the river, and their abundances," she said. "We're still seeing changes within the river's morphology. It'll take a few more years to go back to its natural state, or potentially a better state." Sasak said she also looks at the index of biotic integrity scores to determine the river's health and condition of the fish community. "So the higher the score, the better off the health of the fish community is," she said. The Sandusky River above the dam scored "average," which means the river is in fair condition. "In pre-assessment, the river was in very good condition," she said. "It has declined since 2009. We're hoping the score will increase and improve over time." Sasak said she has found channel catfish, flathead catfish, smallmouth bass, minnows, shiners and darters as well as all six species of redhorse sucker. The Sandusky River is the only known body of water where all six species are found, included the endangered species. "Especially during spawning, it's been neat to see all six," she said. Sasek said she's looking forward to continuing the studies until she graduates in May. "I'm hoping this year we'll catch some migratory white bass," she said. Some history Ballville Dam was built on the Sandusky River in 1913 for hydroelectric power generation. The dam was 407 feet long and 34 feet high, and impounded a section of the Sandusky River for about 2 miles upstream, creating a surface area of about 90 acres, according to information from the U.S. Fish & Wildlife Service website. The dam was originally built by Fremont Power and Light Co., which later became Ohio Power Co. The city of Fremont bought the land and facilities in 1959 and repurposed the dam as the city's water supply. State dam inspections noted "progressive deterioration of the dam and associated sea wall" beginning in 1980, which had been ongoing for several years. Ohio EPA issued orders to the city regarding maintenance. In the ensuing years, the dam removal was selected for funding through the Great Lakes Fish and Wildlife Restoration Act using Great Lakes Restoration Initiative funds, the website said. The goal of removal was to restore and expand the self-sustaining fishery resources within the lower Sandusky River by providing fish passage at the impoundment site upstream and downstream, and to restore system connectivity and natural hydrologic processes between the upstream and downstream portions of the river, resulting in a net gain in the amount of free-flowing riverine habitat for fish and wildlife. During those intervening years, Mike Wilkerson, fish management supervisor for ODNR Division of Wildlife's District 2 office in Findlay, said a study was conducted 19 years before the dam was removed. Biologists caught walleye in Sandusky Bay and released them upstream of the dam to find out if they would spawn in the habitat. "We tagged some of them and followed their movement," he said. "We did find larvae, so they did spawn successfully." Eventually, after environmental studies and several years of lawsuits, the dam was removed 105 years after it was built.