Large number dead fish
 

While playing golf this morning at Sweet Gum, nearly all the ponds had multiple dead fish. With multiple groups of vultures eating them. Anybody have a clue what caused this? I assume it was some chemicals put into the water.

From page three of the District Weekly Bulletin for 7/18:

One of the primary causes of fish kills is oxygen depletion in the water, which is more likely to happen during the hot summer months.

Assume………"

It happened a year or two ago on Mangrove, lightning hit the lake and killed all the fish.

Too much copper sulfate
 

Copper sulfate kills the weeds in the ponds. Too much ends up killing some fish. It likely wouldn’t kill them all, but it is temporarily lethal with the changes in oxygen levels.

You are correct !

Not necessarily, but not out of the question.

The most likely explanation is a “ Pond Turnover”. Basically, this is when super cooled water from a thunderstorm falls on a body of water, that super cooled water quickly sinks to the bottom of a pond and forces that oxygen depleted water to rise, that water rises to where the fish are and in a matter of moments, the fish suffocate.

They die, sink to the bottom and a few days later their swollen bodies float to the surface. After a few days, they sink back down and decay on the bottom of the pond.

Normally, the bigger fish die (vs the small ones) as they need more oxygen.

This is typical of late July / August. Bubblers and fountains do help prevent this from happening.

As far as the article and decaying organic matter….thats a stretch, not sure where they got that info.

What you saw yesterday at Sweetgum was nothing compared to about 9 days ago. There were literally hundreds of dead fish lining the banks of the ponds, with a commensurate number of vultures bellying up to the buffet. The strange thing is that there was not a similar issue at either Mangrove, or Palmetto, which are both right next to Sweetgum. Perhaps the runoff from the heavy rains picked up some hazardous chemicals along the way to the ponds there.

Those saying its low oxygen are correct-high heat and no turnover in the water and the oxygen dips. Some ponds have bubblers and they don't have trouble.

Ohiobuckeye
 

That’s what I think very low oxygen because water is getting to warm!

Thank you for the article.

Could be due to blue green algae also. I’ve seen it in several ponds. When blooms end, the decay of the blue-green algae consumes much of the oxygen in the water, causing fish to die.

Please remember your irrigation water comes from these places.

Maybe they died of old age?:angel:

Only way you will ever truly know why is to test the water for toxicity, heavey metals, is there a sewer line leading into the pond. Never trust the "officials".