Abstract
ABSTRACT We studied the two-story rainbow trout fishery and its influence on zooplankton communities in Big Watab Lake, Minnesota, in 1993. The main trout diet components were Chironomidae (larvae and pupae) and Daphnia pulex > 1.3 mm (53% and 37% dry weight, respectively). Smaller trout were more dependent on D. pulex. Trout consumption of large D. pules peaked in May (50% of diet) and decreased dramatically as the season progressed (3% of diet in August), being replaced by Chironomidae. This size-selective predation influenced the mean size of D. pulex in the water column, with 3% > 1.3 mm in May and 64% > 1.3 mm in September. The change in trout diet was associated with changes in vertical distribution of trout (detected by sonar surveys) as the lake stratified in mid-June. By August, trout were restricted to the thermocline and Daphnia found refuge from predation at greater depths. Results from a creel survey showed Big Watab Lake is providing an excellent trout fishery. Trout stocked at 245±12 (2 SE)...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
