02/12/2021

Seeing The World Through Salmon Eyes

11:59 minutes

three people in water waders walking in a shallow murky floodplain with buckets and research gear
(Left to right) Nick Corline, Miranda Tilcock, and Emma Cox work on releasing the baby fish in a pen during the release of hundreds of baby salmon, hatchery and Feather River raised, into several plots of rice farm. Taken on Wednesday February 20, 2013 at Knaggs Ranch in the Yolo Bypass. Credit: UC Davis

The saying goes, “The eyes are the window to the soul.” But for fish, the eyes are the window to the stomach. 

As one California biologist recently learned, the eyes of Chinook salmon are like a tiny diet journal of everything it ate. But to read that journal, you have to peel back the layers of the eye, like it’s the world’s tiniest onion. 

Miranda Tilcock, assistant research specialist at the Center for Watershed Science at the University of California, Davis talks to Ira about why she goes to such gooey lengths to understand what these salmon eat. Check out a video and photos of the lab’s research below! 

black and white photo of spliced orbs with frayed layers peeling away from the edges like an onion
Dissection of a tuna eye. Credit: Carson Jeffres
a circle that is slightly opaque and has cracks, lines, and small little bubbles. in the middle is the word "core"
The eye lens of a hatchery fish under a microscope. Credit: UC Davis
a man in a baseball cap and wearing gloves dissects a fish on a lab bench outdoors
Carson Jeffres peels the eye lenses of a fish in Brazil to learn about its life history. Credit: Courtesy Carson Jeffres/UC Davis
a woman in glasses and a beanie holds a large fish
Study lead author Miranda Tilcock pioneered a technique for freshwater fish that involves peeling its eye lenses to reveal its dietary and habitat history. Here, she holds a salmon. Credit: Courtesy Miranda Tilcock/UC Davis

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Segment Guests

Miranda Tilcock

Miranda Tilcock is an assistant research specialist in the Center for Watershed Sciences at the University of California, Davis in Davis, California.

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Segment Transcript

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Meet the Producers and Host

About Katie Feather

Katie Feather is a former SciFri producer and the proud mother of two cats, Charleigh and Sadie.

About Ira Flatow

Ira Flatow is the host and executive producer of Science Friday. His green thumb has revived many an office plant at death’s door.

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