Apr 23, 2014

Mysterious fish kill on the Tamiami

What caused these fish to die?

About a hundred bass were spotted floating in the canal.

Low dissolved oxygen levels associated with springtime
warming of the canal water caused these bass to die

By the time we arrived it stank and buzzards were on the scene.

At first puzzling was the many gar swimming below.

But that ended up being the ultimate clue:

Gar can surface and gulp air.

The same water was no problem for the gar:
They can gulp air.

Bass can't.

Why they died in only a short half mile stretch of canal and nowhere else is the next mystery.


Gohydrology said...

Someone responded by email: "Actually that's not an common in overcast conditions for big bass to follow a food source to a area that they can't survive on the low D.O. levels. A few good days of overcast and wham a bright sunny hot day and all the big one's float in a little canal like that."

Gohydrology said...

That could explain it: there are deeper portions of the canal to the east (closer to 40 Mile Bend) where bass could still survive. The section of canal they died in is shallower (only a few feet).