GREAT OUTDOORS: Stone Lab project measures invasive goby's impact

Ohio State University's F. T. Stone Laboratory on Gibraltar Island in Put-in-Bay offers scholarships for highly qualified students enrolled in classes each summer through its Research Experience for Undergraduate (REU) program. Dr. Justin Chaffin, Stone Lab's research coordinator, said that 150-200 students apply each year for this highly competitive opportunity that currently offers four mentored REU projects conducted in the Lake Erie Islands area. On July 24, the four students gave their oral reports via PowerPoint presentations in the classroom building's conference room that were aired live via Zoom and recorded. The topics included some of the environmental conditions affecting Lake Erie algal species; habitat vs. insect prey availability for Lake Erie island bats; microplastics in Lake Erie fish; and the status of the threatened channel darter in the Lake Erie Islands. The project that interested me the most was conducted by Anna Sedlock, a student at the University of Montana majoring in Aquatic Wildlife. Her work was entitled, "Influence of Round Goby on Native Darters in Lake Erie, with an Emphasis on Threatened Channel Darter." Dr. Brian Alford, Stone Laboratory's assistant director, was her project advisor. Round gobies were introduced into the Great Lakes in 1990 by transoceanic ships and their impact on native fish was observed soon thereafter. Some of those affected include smallmouth bass, mottled sculpins and members of the perch family, namely darters. To search for their presence, groups of students seined using standardized methods at 15 sites on Lake Erie islands where museum records showed darters had previously been collected. In 35 sampling trips, 10,905 fish were caught and identified. Round gobies dominated the catch with 7,967, or 73 percent, being this invasive exotic species. Refreshingly, there were 308 darters captured, including 240 logperch, 55 channel darters and 13 Johnny darters. Channel darters were caught at three of the 15 sites: Kelleys Island's Marina Beach and on South Bass cobble beaches at the Miller Boat Line's Lime Kiln Dock and the state park. To test whether gobies affect logperch behaviors, observations in aquariums revealed little interaction between the two species, with no signs of bullying or intimidation. Logperch numbers have been declining for about 30 years, longer than gobies have been present in Lake Erie, so the cause is more likely the result of unrelated environmental changes. They include more algae-covered rocks due to deeper sunlight penetration from zebra mussels' water column filtration and higher nutrient level concentrations that are causing more frequent occurrences of low dissolved oxygen levels. Stone Laboratory is celebrating its 100th anniversary of the donation of Gibraltar Island for the location of the biological field station by longtime Ohio State University Board of Trustee member Julius Stone in 1925. Facilities such as Stone Laboratory give students hands-on training using the latest methods, which is undisputedly the most effective form of education. The REU program is the consummate example of this practice. The quality of the work performed by the REU students continues to be remarkable and helps answer ecological questions in a timely manner. Targeted donations can be made to help support the REU program or any other of Stone Laboratory's operations. See https://ohioseagrant.osu.edu/giving This can allow more research, education, training and outreach efforts to better serve those who cherish Lake Erie and appreciate clean water and a healthy fishery. There is a free open house Saturday, September 6 with tours of Gibraltar Island and the South Bass Island Lighthouse. For details, visit: go.osu.edu/SLopenhouse