Movement Patterns of Stream-Resident Cutthroat Trout in Beaver Creek, Idaho–Utah

Abstract

We used mark–recapture, radiotelemetry, and two-way traps to determine daily, seasonal, and annual movements of cutthroat trout Oncorhynchus clarki in Beaver Creek, Idaho–Utah. We recaptured 26 of 167 (16%) passive integrated transponder (PIT)-tagged cutthroat trout; 16 of the fish were recaptured less than 300 m from the point of capture 1 year earlier, whereas 10 fish were recaptured a median of 1,407 m (range 331–3,292 m) from their captured point of the previous year. Radio-tagged individuals moved less frequently and shorter distances (median = 0 m) during autumn and winter, more frequently and farther during spring in association with spawning (median = 576 m), and variably and sporadically during summer (median = 55 m). We found substantial local movements during a diel period that would not have been found using a once weekly observation period. Frequency of cutthroat trout movement through two-way traps was greatest in July and early August and had stopped almost entirely by early September. Movement timing and frequency were similar between the traps and the radio-tagged fish. Our results demonstrate the mobility potential of cutthroat trout and the importance of selecting appropriate spatial and temporal scales of observation when studying their ecology.