Update with a new hypothesis. My original observation last year was:

 Quote:
Originally posted by Theo Gallus:
This year when I feed the fish (I throw in about 4 lbs of Purina GFChow by hand about 4 times a week) over the deep hole at the south side of my pond, I have not been able to identify the very first fish that hit the feed. I am used to the "wham-turn-tail slap" of Channel Cats, the hit, run, and nibble of GShiners, and the lazy-day surface-swallow-submerge cycle of the Grass Carp. This is none of those patterns. It seems to be caused by fish intermediate in size between my 6"-9" GShiners and the 18"-24" CC. It is very quick, very violent, and virtually impossible to see the fish responsible (one time I thought I saw a tail with a lateral line, hence the idea it might be LMB). There are only a few hits like this right when the feed hits the water (tonight, three separate hits simultaneously), then, after the bigger CC show up, not again.

I have heard the decription of HSB "exploding" onto the feed; this is kind of like that, but 1) I only have one HSB that I know of and 2) I believe the strikes are too small to be caused by an 18"+ HSB.

Any ideas what is responsible? Possibilities among the stocked fish that have not been seen feeding are redears(very doubtful), BG, HBG, and LMB.

Cecil or others with feed-trained LMB - Do they hit the feed like this?
I have observed the "mystery feeders" again this year and I think perhaps I have them ID'd. I think they are small (6"-12") CC, based on a good visual ID of one tonight that went through some real acrobatics to apparently avoid being eaten by a LMB (which hang around the feedring looking for snacks much larger than a pellet, as Meadowlark and others have noted).

The mystery feeder sound/splash signature seems to match this size CC, so maybe that's it. I never considered small CC last year because 1) I did not know that my CC had successfully reproduced and 2) my original CC stockers did not act like that while feeding when they were the same size. But I now know my CC have indeed spawned, and think the first year class was in the 6"-9" size range last year. And my original stockers, when that size, had no predators in the pond even close to their own size, let alone big enough to eat them. But a 6" CC in the pond now has to worry about 2-3 lbs LMB, hence (I speculate) the change in pellet feeding behavior.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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