They can lie dormant in extremely cold water temperatures, yet warm water temperatures over seventy-five or eighty degrees can often be fatal. Trout will seek cool water sources when water temperatures become warm. Cold underwater springs and cool feeder creeks are areas where trout will migrate during periods of warmer water. With this in mind, a thermometer is a very useful tool. Taking water temperatures will help find areas of a river where temperatures are more favorable.
Trout feed most active in water temperatures between fifty and sixty-five degrees.
Remember to look for favorable water temperatures and good oxygen. These areas are also vital to insect life which trout feed on. Fishing in water temperatures exceeding seventy degrees can be stressful for these fish. Always handle them delicately and quickly release them . Food is obviously an important aspect to trout survival as in any living organism.