The Importance of Day Versus Night Fish Sampling for Instream-flow Determinations
Developing and recommending protective flows for stream fishes requires precise information on how fishes use their habitat. Collections to establish fish-habitat relations are typically conducted during daylight hours, but because of diel habitat shifts exhibited by many warmwater stream fishes, we were concerned that determining protective flows only from day collections would result in recommended flows that were not protective. We tested for diel differences in habitat selection by stream fishes and evaluated the effects of these differences on simulated usable habitat area as flows...
