Here's my hypothesis on why I'm experiencing the death of some of my smallmouth and bluegills, but very few largemouth or yellow perch in my multispecies pond. This could explain
Glenn's losses also.
The smallmouth, although pellet trained, I've observed tend to go off of the pellets, and may do so because of the aggressive feed trained largemouth bass, or simply that their species has a tendency to do that. And I've observed may of the bluegills in the pond either aren't interested in the pellets, or don't stay on the pellets due the agressive largemouth bass or again some other reason.
The smallmouth only have an average condition factor and the bluegills appear quite thin for the most part. I've even take a few bluegills though the ice that seem to be stunted (large eyes) which suprised me due to all of the predator fish present. However numerically there are not a lot of bluegills.
Conversely the largemouth bass and yellow perch* that seem to stay on the pellets have a higher conditon factor going into winter on into feeding resumes in spring.
So I believe too many fish and too many species are competing for whatever natural feed is present (pellet fed fish feed on some natural feed too) and the fish that are not pellet fed aren't getting enough feed to sustain them through winter or keep them strong enough to combat stress.
I'm not planting perch or bass into the pond this year, and will attempt to remove as many smallmouth bass as possible by angling and electroshocking. I will also probably drain the pond in the fall and start all over in the spring.
*Note: if you have read any past posts where I believed the yellow perch did not stay on pellets I now believe that was incorrect. I have had the chance to open up a few this spring and noted fatty deposits in their body cavities. I only see this in fish that are regularly fed artificial feed. Apparently they are feeding on the outskirts of the largemouth bass or feeding after the largemouth bass have quit feeding.
