Laserfiche WebLink
<br />16 <br /> <br />RESULTS <br /> <br />Winter and Summer 1981 <br /> <br />Seasonal distribution <br /> <br />One of the original purposes in conducting this study was to <br /> <br />detennine if differences in fish microhabitat choices existed <br /> <br />between the winter and summer seasons. During the study, a large <br /> <br />difference was observed in the general microhabitat choices of <br /> <br />both rainbow and cutthroat trout between the two seasons. <br /> <br />Winter <br />-t During the period from January through mid-April (the time <br /> <br />of lowest water temperatures, hereafter referred to as winter), <br /> <br />the fish were found heavily concentrated in large deep pools and <br /> <br />in quiet back-eddies. It was not unusual to observe several hun- <br /> <br />dred or more fish within a pool. Their primary activity within <br />th~ pools was random swimming, although stationary swimming was <br />observ~d along sheer edges and in pool thalwegs. (A sheer edge <br />is an area where the velocities change markedly.) While engaged <br /> <br />in random swimming, fi sh were usuall y di stributed three dimen- <br /> <br />sionally with no evidence of territoriality and small distances <br /> <br />among fi sh. Fi sh engaged in stationary swimming exhibited both <br /> <br />three dimensional and vertical two dimensional distribution along <br /> <br />sheer edges. The distance among fish was again low and evidences <br /> <br />of territoriality were rare. <br />