Brian Roth Salmon
Brian Roth shows off a Chinook salmon, a popular sport fish and top predator in the Great Lakes.

In Episode 13 of Illinois-Indiana Sea Grant’s podcast series Teach Me About the Great Lakes, titled “It Smells Like Science,” host Stuart Carlton interviews Brian Roth, an ecologist in the Department of Fisheries and Wildlife at Michigan State University. Roth studies food web structure and function to try to understand how fish management and harvest actions affects the food web and vice versa.

headshot of man wearing red polo, surrounded by trees

Brian Roth

Carlton, IISG assistant director, and Roth talk about predatory fish in the Great Lakes, the history of the Great Lakes salmon fishery, how native and invasive fishes interact within the ecosystem, and how the fish populations are changing as lake conditions change, as well. They also briefly discuss invasive crayfish and the nitty gritty detail of conducting a fish diet study.

Teach Me About the Great Lakes is a monthly podcast in which Carlton—a social scientist who grew up in the South near the Gulf of Mexico—asks people to explain the biology, ecology and natural history of the Great Lakes. A new episode is usually released on the first Monday of each month. The latest episode is embedded below.

Love this episode and want to hear more in the future? Subscribe on Apple Podcasts or Spotify, or use the RSS feed in your favorite podcast player.

If you have questions you want answered about the Great Lakes, reach out to @TeachGreatLakes on Twitter or email Stuart Carlton at jsc@purdue.edu.


Illinois-Indiana Sea Grant is a part of University of Illinois Extension and Purdue Extension.

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Join is in welcoming our new research and reporting coordinator, Laura Esman, to the team! In her new role, Laura will oversee research competitions and manage IISG’s research portfolio. She will also spearhead IISG data collection and lead the program’s annual reporting process.Esman brings over 30 years of experience in research, project coordination and grant administration. Her most recent positions include managing director of the Indiana Water Resources Research Center, and lab manager and research associate in the Natural Resources Social Science Lab in Purdue’s Department of Forestry and Natural Resources.Full story at the link in bio.
There’s still time to register! Educators are invited to join the Great Lakes Region Place-Based Education Institute starting this February and dive into hands-on strategies that connect students with their communities and local environments. Don’t miss this powerful professional learning opportunity!Learn more & register at the link in bio.
🎉 Congratulations to our IISG Knauss Fellowship finalists! We’re proud to announce Anupama Chandroth (@iubloomington) and Laura Gray (@illinois1867) as Illinois-Indiana Sea Grant’s finalists for the 2026 Sea Grant Knauss Fellowship.They’ll join a national cohort of 48 finalists placed in executive and legislative branch offices in Washington, D.C., contributing scientific expertise to federal decision-making on marine, coastal, and Great Lakes issues.Full story at the link in bio.