There is a creek close to me that feeds into a larger river. It is fed by the swamps surrounding it. The water is always black. It looks like expresso coffee. Its a beautiful river and I’ve caught fish here but they are usually not that plentiful- Mostly bream. Sometimes bass. Yesterday i hooked up with a couple of bigger fish that spit the hook before i could boat them. i caught a bowfin that was around 19 inches. There were a lot of bowfin gulping air in the river. I know they do this to breathe. The bass fishing here is hit or miss. Couild the oxygen levels be so low that the bass are further down river? And does anyone have a way to look at water and tell if the oxygen levels are good for bass?

 

Can't tell dissolved oxygen levels without testing it. You can determine if the DO levels are adequate if other fish like bluegill that require the same water temps and DO levels as bass are present.

Carp and bowfin can't breath air, what you may be seeing is fish feeding on something on the water surface.

Tom

Bowfin and gar gulp air and fill their swim bladders with it. The swim bladders work like a lung for them because of how the capillaries surround the lining if the swim bladder. There are no signs of blue gill or break.  “The bowfin is the only remaining member of an ancient group of fish which lived over 180 million years ago.  The bowfin has several features similar to a gar.  The head is covered with bony plate-like armor and much of the skeleton consists of cartilage.  Bowfin can survive in poor water quality with low oxygen levels by breathing air directly into its swim bladder that will function similar to a lung.  Anglers enjoy the strength and endurance of the bowfin, but not the taste.“ (http://www.dnr.sc.gov/fish/species/bowfin.html). The Wikipedia article explains it better. They are a really cool fish. But I’d rather catch bass!

Is it the river you are trying to fish or the creek that runs into it? Rivers usually have lots of oxygen. The creek might not if it's a slow drain from swamps. I dont think you can tell by looking at it if there is a lot if oxygen. Usually rivers have plenty though. The current causes turbulance that basically aerates it like a live well. At least that's what I've been told. 

I’m fishing the creek that feeds the river. Further downstream the fishing is good. It’s tidal too. The murkiness of the water is pretty extreme. A chartreuse spinner bait disappears when it’s 6 inches deep. Thanks for the help.