Tracking Diurnal and Seasonal Movement of Brown Trout in the Little Juniata River

Elaine Langone Center, Terrace Room

As anthropogenic influences continually alter the natural state of the aquatic environment, species become increasingly susceptible to varying ecological conditions. To track the behavior of brown trout (Salmo trutta), researchers from Juniata College implanted Lotek NTQ-6-2 transmitters into 45 brown trout from the upper, middle and lower parts of the Little Juniata River. We recorded the location of the fish twice a week for one year by driving, walking and sometimes kayaking the river. We conducted habitat surveys at several points along the river including the three study sites, and measured average distance to cover; average flow; percent pool and riffle; and the percent of different substrate types. To identify temperature changes along the river, we attaching temperature loggers to kayaks and floated a 26-mile stretch. We found that tagged trout were not found in stretches of the river warmer than 72º C. We also set up stationary data loggers for 24-hour periods at several sites to record daily movement. Brown trout displayed highest movement during dawn and dusk. We found significant difference in site fidelity across the three study sites, and we attributed some if this variability to difference in habitat quality. We also found that site fidelity varied by season. During the spawning period (October, November and December), fish from two of the sites showing lower site fidelity and an increase in site fidelity at the third site. Again, this difference could be explained by habitat variability. Finally, we plan to compare fish distribution with other factors such as land use/cover, distance to closest tributary and macroinvertebrate density and diversity at the study sites.