CHICAGO (CBS) — Some researchers have had a “Finding Nemo” moment in Burnham Harbor.

The Shedd Aquarium’s Solomon David says they look to see what’s happening under the surface of Chicago’s harbors all the time and this week it was anything but routine when they spotted thousands and thousands of gizzard shad gyrating and pulsating in a huge ball.

David says it was a rare find

“We see everything from bullhead catfish and sort of a ball of the young catfish running around the adults. We have seen salmon nowadays that have kind of moved in that at least attempt to spawn even though the habitat isn’t there. There is also some steelhead out there,” said David.

As to why they were there, David doesn’t know. He says we look at Lake Michigan and don’t think about what’s going on under the surface but we need to because healthy fish indicate healthy water.

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