Back ground is I have a 1 acre pond, West Central Ohio, bottom diffuser, pond is 6-7 years old, all contained watershed, no inlets or any other nutrients, pond is 8-10 ft at summer depths, clay bottom and I feed every 3 days ( PGFC)

About 7 weeks ago we hit one of our hottest dry spells and on the very hottest day, I had 3 adult HSB die, all between 19-21" ( this is my oldest year class of hsb) I also have 14-16" and also this years at about 7-8"

Over the next 10 days even though the water temps rebounded from 83 back to high 70's, I lost 3 more adults and noticed that two of them had sores on there sides but I wasn't sure if that what caused them problems or if it happened afte the death.

Jump forward to last night as my buddy caught several of the HSB and the 2 smaller year classes were fine but both bigger fish he kept along with a bigger bluegill all had sores on there sides, see pic below....




so can anyone tell me what or how to treat?? I certainly do not want to restart.... all catfish and YP and BC are fine from what I have seen.

Another clue is this year in the pond, I had some American Pondweed show up, not in big numbers but it was new this year ( Damn those Herons...)
Salmonid

The deaths in hot weather could be catch and release stress, HSB are very susceptable to catch and release mortality when the water temps are above 82 degrees.

The sores could be from a bacterial infection, fungal infection, or some sort of parasite.

Here is an old brochure on things that affect fish in Nebraska.

http://lamarck.unl.edu/hwml/pdf-files/bugging-fish3b.pdf

Sores are most likely due to stressors. Like was said above, C&R, etc., when O2 levels are lowest.

If that's not the case, then a couple of questions.

You said you had an aeration system. Was it spec'd out for your pond or was it one that was purchased or a put together DIY system? If it was spec'd. out, did anything change in the pond from time it was installed to the fishkill?

What was the water clarity when it happened? If the clarity was less than 24"-36" what was it due to? Clay or an algae bloom?

Large HSB are more intolerant of low O2 levels than the other fish in the pond. Boiling it down, it might be that there is too much biomass in the pond for the conditions.

You say 1 ac. How many pounds of fish do you think are in there?

um ok I just replied a huge answer and it seems to be gone.. annoying.. Ill have to reply again when I have another 30 minutes. here is short version

Basically I feel the biomass is top heavy and we have taken out 3 big channel cats of 11, 9.5 and 8+ lbs and another 6 lbs of HSB just in the last two weeks.
No fishing pressure during the heat of the summer,

Problem is CC, they spawned and are a HUGE part of the biomass and are hard to get rid of but we been removing everyone we catch for the last two years, probably 50 lbs this year and about 60 lbs last year Im guessing. Pond is more like .75 acre now and its a 1/5 HP Vertex system that ATAC set me up with, no probs the last 3 years when it was waaay hotter then this year.

Salmonid

Oh yeah, water clarity is always clay particle heavy so more like a foot almost always, in the last week its maybe 18"

Salmonid

K. If the CC will come to feed, maybe try to cast net them when they're feeding.

Next year, see if you can pull out whatever they are using for spawning structure - they are cavity spawners.

As Esshup said something is stressing them. It's mostly about water quality which can suffer if you are feeding too many fish.

Your abundant catfish could be making your water turbid.

Yeah I was fixing to say I don't think it's the heat. It gets REAL hot here in Arkansas and I have not had any issues with my HSB, I too have a 1 acre pond but I do not have anything in it but BG, HSB, LMB and a few RES and out of those only the HSB and BG feed. Course my HSB are not 21 inches yet either. Mine are 17 inches. It does sound to me like your hurting for space! Like the guys said above not enough room equals STRESS. Like 12 people being in a elavator!! How long are you going to be in that elavator before you start freaking out!!

I feel your pain.

Sorry to jump topic a bit, but RC51 are you sure NONE of your LMB are feeding?

Mine weren't initially but over the past 3-4 months I've had more and more joining in on the party. My pond is 2 acres and I feed on the East end of the pond (kidney bean shaped). Using a pellet-fly (panty hose wrapped)at feeding time to sample my HSB for growth, I'll catch as many LMB as HSB. Also, the LMB caught on the East end of the pond are clearly fatter & bigger than those caught on the West end of the pond (I'm feeding the HSB AM LMB food as they're now at +/- 15").

Just curious if you're sure none of them have taken to pellets. I've even noticed they'll hang out under the feed rings I have for the BG. They'll come up for pellets once in a while and I would imagine grabbing an ocassional BG "snack"

Hey LL,

As far as I know they are not. I have never caught one on a pellet or seen them hit pellets. I also have them all around my feeder but they are there only for one thing far as I can tell and that's to take a life or 2 if they get a chance!! Now that don't mean a smaller one or 2 may be eating pellets??? But I don't think so...

RC

Can you get a good clear pic of the sore area ?

Most likely is stress related and likely a water quality issue (to near carrying capacity and feeding).When big fish compete at the feeder they bump around and into each other. This can cause areas that get bact. or fungus infection.

It sounds like you have to many fish especially big ones in that size pond.

Looks like you need to get your buddy and his little girl over to fish em out

I hope to get some fishing in over the next week since winter has pretty much showed up, now I can target my gills, crappies and YP and see if anything else is infected, Ill be taking more specific pics and continue to remove all cats. Also forget the cast net, Im a professional with one ( fish catfish tourneys year round and can throw a net in my sleep) Im telling you, you get 1 shot at them and many times I figured Id have a dozen and only get 1, they are really fast and once you make 1 throw, they scatter for 2-3 days and wont come on the feed.
Jeff, anytime, come on over!! LOL

Toying with pulling my cover, but mostly cedar trees on there sides to encourage crappies and YP to spawn. there is 1 HUGE stump in the bottom of the pond and too big to come out so I figure there burrowing under the cedars, lets face it with mother nature, if there's a will, there is a way..... They have proven it.

Stay tuned for more updates...


Mark