thumbnail

A comparative and experimental evaluation of performance of stocked diploid and triploid brook trout

North American Journal of Fisheries Management

By:
, , , ,
DOI: 10.1080/02755947.2012.728172

Links

Abstract

Despite numerous negative impacts, nonnative trout are still being stocked to provide economically and socially valuable sport fisheries in western mountain lakes. We evaluated relative performance and potential differences in feeding strategy and competitive ability of triploid versus diploid brook trout Salvelinus fontinalis in alpine lakes, as well as behavioral and performance differences of diploid and triploid brook trout in two controlled experimental settings: behavioral experiments in the laboratory and performance evaluations in ponds. Across lakes, catch per unit effort (CPUE) and relative weight (Wr ) were not significantly different between ploidy levels. Mean sizes were also similar between ploidy levels except in two of the larger lakes where diploids attained slightly larger sizes (approximately 20 mm longer). We observed no significant differences between diploids and triploids in diet, diet preference, or trophic structure. Similarly, growth and condition did not differ between ploidy levels in smaller-scale pond experiments, and aggressive behavior did not differ between ploidy levels (fed or unfed fish trials) in the laboratory. Independent of ploidy level, the relative performance of brook trout varied widely among lakes, a pattern that appeared to be a function of lake size or a factor that covaries with lake size such as temperature regime or carrying capacity. In summary, we observed no significant differences in the relative performance of brook trout from either ploidy level across a number of indices, systems, and environmental conditions, nor any indication that one group is more aggressive or a superior competitor than the other. Collectively, these results suggest that triploid brook trout will offer a more risk-averse and promising management opportunity when they are stocked to these lakes and elsewhere to simultaneously meet the needs for the sport fishery and conservation objectives.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
A comparative and experimental evaluation of performance of stocked diploid and triploid brook trout
Series title:
North American Journal of Fisheries Management
DOI:
10.1080/02755947.2012.728172
Volume
32
Issue:
6
Year Published:
2012
Language:
English
Publisher:
Taylor & Francis
Publisher location:
Philadelphia, PA
Contributing office(s):
Utah Cooperative Fish and Wildlife Research Unit
Description:
14 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
North American Journal of Fisheries Management
First page:
1211
Last page:
1224