Temperature is huge for the survival of most organisms. For example, many fish are stenotherms. This means that they can only tolerate a small range...

Temperature is huge for the survival of most organisms. For example, many fish are stenotherms. This means that they can only tolerate a small range of temperatures. These fish will move if temperatures get too hot. This is a big issue for fish like trout because often times they head into small headwater streams to try and find cooler waters. If the temperatures there get too hot, there is nowhere to go. What sort of challenges (e.g., competition) is being forced into headwater streams creates for these stenotherms?