I was wondering what one should do with the fluctuating temperatures in coastal NC right now....last week or so the pond water was below 50 and I did not feed the fish. Now, the temp is back up to 56 and I found a partially eaten fish at the bottom of the pond when I cleaned out some debris. Are my fish starving to death and resorting to cannibalism? Should I feed them for a few days, and then stop when the temps. start to drop again??
Your fish are not starving to death. Your half eaten one was probably eaten by one of your famous NC flying predators like an egret, heron, or maybe even a walking and furry one like a raccoon. Do not feed them. They are still hibernating and will not be able to eat until the temps are above 55 for a long time.
The pond is covered completely with chicken wire. No predators can get in now (although the reason it was covered like Fort Knox is because of a heron, who I caught in the act, and a raccoon, who polished off my biggest fish, and left some droppings. We had it covered with a net, but the heron broke through the net, punching in a big enough hole to gobble up some fish. The raccoon came a few days later and took advantage of the hole, which we did not realize was there.)
So, the fish left are VERY active right now, not listless at all, hanging around the top of the pond right now with our warm weather. They are quite still and deep when the water is really cold. I did feed them today.
So, what do you think about the dead fish now? My guess is a heron or raccoon would not leave anything behind. This fish (about 4 inches long) had its middle eaten away....
And what do you think about the hibernation theory, given the activity of the fish? It's a very confusing weather pattern we have right now, with the temps in the low 70s, and not getting too far below 55 at night. Next week, who knows?
I understand your wish to feed your fish, but please don't. It could be that the dead fish was sick from getting something to eat and not being able to digest it, so he died. Feeding fish in the winter can kill them quickly. If you want to double check, go to koivet.com and have a look. You will find that fish cannot survive being fed in cool weather. Do you have goldfish or koi? Neither needs feeding in the winter, but koi need to be fed in the summer.
I have goldfish.
So, do the alive fish eat their dead? I've actually never seen a fish eaten like this is my pond. Sure, I have found plenty over the years, in all seasons, die and float to the surface, but never eaten like this.
Yes, all fish will eat other fish. In fact, fish will kill a sick or weak fish. I think it is a way they have of keeping the school hardy.
Your goldfish will be just fine if you never ever, feed them, even in the summer. Just balance the pond ecologically with submerged vegetation and make sure your bioload is not too high and you can just relax and never have to clean fish poop out of your pond except in your yearly cleaning.
Ten Laws of Pondkeeping
This should give you a few ideas about keeping your pond balanced so your fishies stay healthy. Sounds like you are doing a good job.