Temporal and spatial relationships in the movements of loch dwelling brown trout, Salmo trutta L., recorded by ultrasonic tracking for 24 hours

Publisher Website
Google Scholar
Abstract
Ultrasonic telemetry was used to record simultaneously, over one complete April day, the movements of four adult brown trout, Salmo trutta, which were residents of a shallow Scottish loch. The daily movements were generally along linear tracks. The home ranges are described as standard and 95% confidence ellipses. The area of standard ellipses ranged from 330 to 633 m2 while 95% confidence ellipses were larger, ranging from 513 to 979 m2. The distances separating individuals, which ranged from 1 to 70 m, were greatest during peaks of activity. Although there was considerable spatial overlap of individual home ranges, the trout were not within visual range for most of the tracking period. Close encounters (proximity <2.5m) occurred most frequently and lasted longest at night. It is concluded, from this study, that brown trout in small productive lochs are solitary but may hold temporary station within widely overlapping home ranges.