Did you know that trout are cold blooded? What does that mean, exactly? Well, it means that their body temperature depends on the temperature of the water in which they swim.
Why is this important to consider? If the water is too warm, trout struggle to thrive. Warm water carries less dissolved oxygen, which means it is harder for them to breathe. Think of the last time you hiked at an altitude higher than you’re used to and how hard you were breathing. This is the same for trout when the water warms.
And when you catch a trout when the water is too warm, that is akin to running a marathon at 10,000 feet, or even higher. It is harder for them to recover, and at times, they don’t and succumb to the stress.
Check in with your state’s wildlife management agency for updated info and regulations. Remember to take the temperature of the streams you’re fishing this summer to find out if it is safe to fish. If not, go higher and check the temperature again. Or fish only when the weather is cool in the mornings. Or fish for a warmwater fish like bass.
Take a photo of this thermometer and do your local fishery a favor to keep our beloved trout safe and alive this summer.
Of course, not all trout, and certainly not all fish, are affected at the same temperatures. Generally what’s good for rainbow and brown trout is not cool enough for cutthroat and bull trout nor mountain whitefish. Keep in mind this nuance and use your best judgement. If you observe fish acting sluggish or if you find them in really deep holes and not eating, it is likely too hot to fish for them.