Pond Boss Forums INTRO Questions & Observations Large Tilapia Deaths, first observed

Over the past week, I have pulled 7 large dead tilapia from a pond in NE Florida all in the 18" & 4# range. The buzzards disposed of 6 & the 7th just completely disappeared overnight. Deaths, I suspect from stress from the recent cold spell & old age. The lowest the surface temps got was 60 degrees? I do understand that most all dead fish go to the bottom of the pond but I am surprised that I have not seen at least a couple of small dead tilapia floating near shore. Perhaps they were all eaten when they got slow from the cold? The smaller are supposed to be more sensitive to the cold. The smaller fish would be from a more recent & different stocking, more pure blue tilapia genetics & they are still swimming? The big boys were always seen when I hand threw food, but never the small tilapia. I did observed a few 6" & smaller hiding near shore.

Comments appreciated.

Any chance the cold air caused the water in the pond to "turn over"?

A low oxygen event is almost always more fatal to the large fish compared to the smaller fish.

The aquatic predators are likely eating everything that fits in the mouth of the predator. You got alligators? Slow sluggish tilapia are very easy catch food items.

I only saw 1 dead TP this year out of the hundreds that died. I know among other things I have at least 2 large snapping turtles that fed well.

The all gators were removed in '23. The excessive turtle herd was culled in '24 with enough left to do the routine garbage removal.

FishinRod has the answer, I believe: The weather caused the water in the pond to "turn over"? A low oxygen event is almost always more fatal to the large fish compared to the smaller fish. I never consider this!

We had a stretch of cold weather from about 12 Jan till 25 Jan this period included a heavy rain storm 4-6". First floater seen 27 Jan with little decomposition, next 6 dead Tilapia about 30 Jan, & the last 13 on the 4 of Feb. Each new group was more consistently decomposed than the previous & leads me to believe they all died about the same time; went to the bottom & later decomposition gases brought them to the surface. They varied in length from 12" to 22". No small tilapia have been seen nor CNBG.

A low oxygen event is almost always more fatal to the large fish compared to the smaller fish. I had a similar event happen years ago. A 10 day stretch of hot cloudy days & excessive amount of weeds in the pond. The low oxygen killed about 36 fish in the 3-4# range. Other ponds in the area had a similar problem.

This is my story & I am stickin to it.

I have some tilapia starting the Fall "death march" and dying in Northwest Ohio. Water temperature 48F. I think these TP are hybrid blues of males- females that originated as hatchlings in January 2025 from a TP farm in Florida. Some are as large as 2.25lbs. Lots of growth for 11 months old. It would be nice if BG grew that fast. However if one wants big panfish fast get some tilapia. Most of the biggest ones I have been catching have been males. The bite started back in September with water temperature around 73F some were 2.0 - 2.2 lbs back then as 9 months old. Not much growth occurred when the water temperature dropped below 65F.

Thanks Bill for the good report.

If we get enough reports documented, then pond owners should be able to figure out the rough dates for tilapia activities relative to latitude in the U.S.

"Death march" is a good description, same for me in central Ohio. I wish I could catch all the ones I put in. They grow fast, are fun to catch but a real challenge to catch - I only catch about a 1/4 of them.