I caught this bluegill from my pond that has sores on one side. I've caught some others like this and was wondering if anyone knew what causes these sores? One side is all beat up and the other is really clean with only one small spot.

Could be birds pecking at it. It could also be a rash of some sort caused by a allergy or something else. Just my guess.

It appears to be white grubs or another grub parasite. They are a fish parasite that has a life cycle involving snails, birds, and fish. They are difficult to remove from a pond. You have to disrupt the life cycle of the parasite. It is not a problem for human consumption, but is not very appealing. Introducing redear sunfish has been effective in some ponds since redear eat snails.

Yet another reason to love the TFF! Some very smart anglers post here.

Excellent post. x2

I have corrected the parasite problem using red ears in one 4 acre pond. They really get after the parasites. For some reason that escapes me, in this particular 4 acre pond my initial stocking of red ears did not take and I had a lot of fish with the same markings on the copper nose as shown above. Re-stocking red ears fixed the problem over a couple of years.

By the way, the best source I have found for red ears is Tyler fish farms. They sell their copper-nose blue gill with a 15-20% mixture of red ears. Excellent for pond stocking.

If you've ever been wading, swimming or float tubing in a lake or pond and find that you're itching places on your body that look and feel like chiggers have been feasting on you, that is caused by a parasite that is present in waters that don't have redear sunfish. Redear eat those parasites.

Guys - thanks for the great information. Really helpful in solving the issue. I'll try to put in some red ears and see if it fixes the issue. Are there any side effects with red ears?

Side effects? No. They are great eating, aggressive fish , and grow to excellent size and beauty.

the major side effect is that you will have some brute sunnies that will strip drag when using ultralight.

There are lots of side effects, but can't think of any that are negative.