The CC can take up a lot, or most of the biomass, if large. I had the same problem last year. One morning they didn't come to feed, and were hanging around the bank. I netted out a few of the stressed ones, dressed them before they could die in the pond. I ran a pump to circulate the water, then immediately started catching out the CC (2 to 5 lbs each). I never had another problem. Last winter the otter attacks reduced the biomass even more. We ate CC last summer until they became "just another meat".
