Stream temperature is one of several ecological settings variables that collectively characterize the biophysical setting of each 30 m cell at a given point in time (McGarigal et al 2017). Several fish species (e.g., brook trout) can only survive in coldwater streams, which have higher levels of dissolved O2, while other fish species are adapted to warmer streams. At the same time, ectotherms such as aquatic insects and fish can develop more quickly in warmer streams. Stream temperature is a coarse classification of streams by mean annual temperature.