Whitefish eating rocks?

[former_yooper]

had fair luck this morning on the Menominee river just below the damn. Saw LOTS of fish in the camera, but was only able to ice 3 of them. 17", 21" and 27". Threw the 27" back in the hole as she was full of eggs. Other 2 were males. Got all 3 on the orange/chart tiger Ice Darter. Had a few more chase very aggresively but would not hit. I believe they are not eating right now just hitting out of instinct or just plain pissed off. Next time I will take pictures to show the fish.

Now my real question....In the Aqua-Vu I was watching a half dozen or so whitefish swim at a 45 degree angle picking up small rocks or pebbles. I laid a few dead minnows down there and they picked around them. Am i seeing things? Am I staring at the camera screen too long and it's making me go crazy?

Scenario: Flat sand bottom. Very little current. dirty or stained water. 6' fow

[The Bait Shop Guy]

I think they are primarily bottom feeders. Most of the ones I clean have small gobys or wigglers in their stomachs. They could be picking at some sort of small invertebrate that's too small to see on the camera.

[raywriter]

I observed the same thing using a camera last Saturday between the Terrace and the mouth of the river. I could see something small waving back and forth slightly - possibly a wiggler or a bloodworm - but I could not get a clear enough focus on this camera to identify it. Anyway while I was looking at it a fish slipped in and grabbed it.