We had our pond redug back in august of 2019 to almost a half acre and 12’ at the deepest spot and feathered back to the banks. Has a mount around the outside to prevent field chemicals and runoff and also has a fountain for oxygen. Restocked with largemouth,hybrid stripers, yellow perch ,bluegill and a coupe grasscarp. Pond has done great until this year. For the past month or so it Seems like everyday we find another dead bass. All heathly nice looking ones.. No other species. It’s almost to the point where I don’t think there is many bass left. All around 15-16”. Fish don’t appear to have any wounds from herons or anything. Just when they get close to the bank the buzzards and crows drag them on the bank and eat them. What in the world could be causing this??

Do you know the water temp and DO level? Are you feeding? Generally, LMB are no more susceptible to problems that the other species you mentioned.

I haven’t checked anything but I’d say it’s no different than any other year. I had fed every year up till this year. So very little feeding this yea because of so many other things going on. Past years in the spring I’d use copper sulfate to keep weeds out and I haven’t even had to do that this year because no weeds.

What size range are the bass that are in the pond biw, and what fish have you harvested from the pond the last few years?

The bass that are dying are 15-16”. There’s no real new ones in there that have been seen it caught. None have been harvested. There was 35 largemouth,10 Hybrid stripers ,50 perch,300 bluegill,50 red ears and lots and lots of minnows and shiners in 2019.

So, you don't have any other size of bass in there besides bass that are 15"-16"? What about all the other fish in the pond? Have any of them have been harvested since being stocked? What size are the Hybrid Striped Bass?

We don’t harvest any fish. Other than you see some small bluegill they just kind of take care of themselves. No smaller bass or perch. Hybrids are maybe 4lbs.

That could be part your problem. Harvesting fish is an integral part of pond management. Ponds have what is called carrying capacity, and they can only keep a certain amount of fish alive for a certain amount of water.

It's a bit strange that the HSB aren't dying along with the LMB. If you haven't reached the carrying capacity yet, then my only other thought is that if you are fishing and catching the bass now in the heat, it could be handling stress that could be causing them to die. If you are fishing, when you catch a fish do you net it and get it back to the water asap or is it dragged up on the bank then put back in the water? What is your surface water temperature now (12" deep) and what is the water temp at the bottom of the pond? You can measure the temp with an inexpensive swimming pool thermometer.

You won't see all the dead fish in the pond, not all dead fish float.

Moving forward, if you don't harvest roughly 10# of bass from your pond per year, and they are reproducing in the pond, then you will eventually end up with a LMB stunted pond.

No fishing. If we took out 10an per year there wouldn’t be any bass left. There’s no small ones seen or caught when it is rarely fished. Only send largemouth. Nothing else. There’s no vegetation in the pond either.

Then that means one of two things. 1) There is absolutely 0 habitat in the pond where the fish can reproduce. or 2) The bass are eating every fish that is being hatched in the pond. Each bass needs to eat 10# of fish per year to add 1 pound of weight. But tehy can add that weight by eating 2# of good commercial fish food. So if you stop feeding the fish in the pond the bass will start looking for a lot more fish to eat. A Bass that is is 15"-16" should weigh around 1 3/4# to a hair over 2# (or more). Next floater that you find that isn't partially consumed, get a weight on it.

If either of those is true, then you are already headed down the slope to a LMB stunted pond.

BUT that doesn't help your bass dying situation now. With no vegetation in the pond, I have to assume you have a phytoplankton bloom? What is your water clarity? i.e. if you put a secchi disk or white coffee cup on a string, how deep is it in the pond before it disappears from sight? Let us know about your water temp.

I have some habitat that I made from pcv pipe and tube. And some stacked skids. Water Had been super clear in the past but this year is not as clear but not cloudy.

Based on past work carrying capacity in the south in newly stocked ponds is reached at about 18-24 mths while up north the period is a bit longer 24-30 mths.

Are you saying there is no reproduction (no small young fish)?

Assuming they get ate by everything eventually. Never see any little bass or perch. Some bluegills in the gravel around the pond.

You guys (ewest, esshup) have this under control, but my mind says 35 LMB at 1.75lbs-add 4lb HSB, a bunch of perch and BG it sounds to me like some fish need culled asap.

Yup. If the OP doesn't Mother Nature will and it sounds like she is starting now.