In these times - when conditions are just right, what you learn here may not work. When this happens - please be kind in your thoughts of me and my words. The brain of a trout is a simple one. This brain will fit on a quarter and it is primeval. The fact that many fishermen give the trout high marks for intelligence just shows how much they don't know about biology.
Simple minds have simple needs.
All species of trout have three basic needs not including water, Food, Shelter, and Oxygen. In order to be a sustaining population they need a proper spawning habitat, which is usually the same as their normal living habitat. They also need deeper pools to survive a winter with anchor ice covering the habitat, unless they are in the southern tail waters of America or other countries. In nature there are seldom any linear relationships. The trout who limit their diet to minnows, sculpins, crayfish and other trout are sometimes called sharks.