Our local TU chapter (in Texas) funded a study of trout movement in our local tailwater. The fish were tracked via radio transponders inserted by a state fisheries biologist (who also performed the tracking study). Basic message was that the fish did not move very far from their initial stocking point and did not move upstream to seek out cooler water as the water warmed in the summer. The biologist excitedly followed one transponder several miles upstream, only to find that it was in an osprey nest.