How Water Temperature Affects Your Fishing
We’ve had some 90 degree days here in Pennsylvania with evening temperatures staying above 70 degrees. That’s hot by almost anyone’s standard. Rising temperatures lead to rising water temps.
Why is rising water temps important? They can be lethal to trout. Why is that? Simply put, they are cold blooded. What does cold blooded mean? Simply put, it’s a kind of animal whose body temperature varies with its environment. Other great examples reptiles like snakes and aligators.
If you practice catch and release and continue fishing freestone rivers and streams when the water temperature gets too high, you run the risk of killing the trout you intended to safely release. So what does water temperature mean when it relates to trout? Should you carry a stream thermometer? At what temperatures will the water be lethal to trout?
A stream thermometer is a very useful tool when it comes to fishing for trout. It could tell you where the fish are holding, how they are feeding and when you should probably switch from a freestone fishery to a tailwater fishery.
If you see trout holding in one place opening and closing their mouths, they are stressed. They are not feeding. They are trying to circulate more water around their gills to get more dissolved oxygen. It’s like they are gasping for air.
As water temperature rises, the amount of dissolved oxygen in the water decreases. Different trout adapt differently and require various water temps. Brook Trout need more oxygen, and thus cooler water temps than rainbows or brown. The optimal feeding temperatures for Brook Trout varies from 45 degrees to 65 degrees. The temperature that a Brook Trout begins to stress at is 66 and the water temperature at which could be lethal to Brook Trout is 70 degrees.
Cutthroat’s optimal feeding and movement water temperatures are 38 to 60 degrees, another species that requires a lot of oxygenated water. When the water temperature hits 61 degrees, the Cutthroats will begin to stress and feed less. The lethal temperature for a Cutthroat Trout is 68 degrees.
Rainbows and Browns are the hardier of the trout family and don’t require the oxygen levels that others do. The optimal feeding and movement water temperatures for them is 45 to 68 degrees. When the water temperature hits 69 degrees, both species will begin to get stressed. If the water temperature continues to rise and gets in the 75 to 78-degree range for an extended period, it can be lethal for Rainbow and Brown Trout.
Checking water temperature to try to protect the fisheries is really important for the fish. It’s our job to protect them and their habitat. That’s it for now my fishy friends, pack it in, pack it out!
Tight Lines and Screaming Drags