Archive for September 12th, 2007

Heat’s Impact on Fish

Wednesday, September 12th, 2007

Passport to Texas from Texas Parks and Wildlife and the Sport Fish Restoration Program

When it’s so hot outside that you can fry an egg on the sidewalk, a lot of us wish for the life of a fish. We’d love to spend all day in the wet stuff. But a fish’s life is no walk in the water park.

When the water’s warmer it holds less oxygen.

Cindy Contreras is in Resource Protection at Texas Parks and Wildlife. She says fish are between a rock and a wet place in summer through early fall because as water that’s been heated loses oxygen; and as fish warm up they need more oxygen.

So it kind of creates a bind, or a squeeze on them, as the water holds less and less, but they continue to need it. Also other organisms in the water, like bacteria and insects, anything that’s living in there is going to be using that same oxygen.

Texas Parks and Wildlife stocks sport fish in reservoirs across the state. And according to Contreras summer heat causes the water in those basins to stratify.

The top layer is warmer and lighter, and rests upon a cooler, heavier layer of water. And typically the lower levels will not have very much oxygen or any oxygen.

And so the fish flounder in the warmer water… which is as good a reason as any to go fishing.

Take them out. Get them before they succumb.

Our show is made possible by the Sport Fish and Wildlife Restoration Program…working to increase fishing, hunting, shooting and boating opportunities in Texas.

For Texas Parks and Wildlife…I’m Cecilia Nasti.