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 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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Celebrate Earth Day with freshwater science and good conversation! Join Illinois-Indiana Sea Grant, the Northwestern Center for Water, Loyola University researcher Tim Hoellein, and IISG’s Sarah Zack for Science Sips: Trash Talk about Chicago Waterways. Learn what research reveals about litter and trash in Lake Michigan and Chicago waterways and what we can do to help.Plus, enjoy Great Lakes trivia games!📅 April 22, 2026⏰ 7–9 PM📍 Sketchbook Brewing Company, Evanston Tap RoomCome curious and ready to test your Great Lakes knowledge!
Looking for a fun way to teach about marine debris? Check out Me and Debry, which is a whimsical, 30‑minute, audience‑participation play created for @UWiscSeaGrant. It helps students explore what marine debris is, why it matters, and how we can make a difference in the Great Lakes.The full script (English) and participation scripts (English, Spanish, and Hmong) are free to use, along with marketing materials for performances.Bring learning to life and start a conversation about litter in our waters!Check it out at the link in bio.#TeachingTuesday
Do you work or live along the Great Lakes coasts? Watch our newly released video series collection, containing several short videos that overview the range of coastal protection options in the Great Lakes, including:- Natural processes in the Great Lakes- Hard coastal protection structures and how they interact with/alter natural processes- Nature-based coastal solutions in the Great Lakes, ranging from green to gray approachesFind our two new video series at the link in bio.