Comparison of triploid and diploid rainbow trout (Oncorhynchus mykiss) fine-scale movement, migration and catchability in lowland lakes of western Washington

• Published in: Movement ecology Vol. 11; no. 1; pp. 1 - 13
• Main Authors: Pease, Jessica E., Losee, James P., Caromile, Stephen, Madel, Gabriel, Lucero, Michael, Kagley, Anna, Bertram, Michael G., Martin, Jake M., Quinn, Thomas P., Palm, Daniel, Hellström, Gustav
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 15-09-2023; BioMed Central; BMC
• Subjects: Acoustics; Analysis; Angler catch rates; Bass; Catchability; Commercial fishing; Creel; Diploids; Distribution patterns; Emigration; Emigration and immigration; Endangered & extinct species; Endangered species; Fish and Aquacultural Science; Fish hatcheries; Fisheries; Fisheries management; Fishes; Fishing; Fisk- och akvakulturforskning; Hatcheries; Home range; Introgression; Lakes; Oncorhynchus mykiss; Oxytetracycline; Risk reduction; Rivers; Salmon; Stocking; Telemetry; Trout; Wildlife; Wildlife conservation; Wildlife management; Canada; United States > US; Ward Lake; Idaho
• ISSN: 2051-3933; 2051-3933
• DOI: 10.1186/s40462-023-00418-w

Abstract
Fisheries managers stock triploid (i.e., infertile, artificially produced) rainbow trout
Oncorhynchus mykiss
in North American lakes to support sport fisheries while minimizing the risk of genetic introgression between hatchery and wild trout. In Washington State, the Washington Department of Fish and Wildlife (WDFW) allocates approximately US $3 million annually to stock hatchery-origin rainbow trout in > 600 lakes, yet only about 10% of them are triploids. Many lakes in Washington State drain into waters that support wild anadromous steelhead
O. mykiss
that are listed as threatened under the U.S. Endangered Species Act. As a result, there is a strong interest in understanding the costs and benefits associated with stocking sterile, triploid rainbow trout as an alternative to traditional diploids. The objectives of this study were to compare triploid and diploid rainbow trout in terms of: (1) contribution to the sport fishery catch, (2) fine-scale movements within the study lakes, (3) rate of emigration from the lake, and (4) natural mortality. Our results demonstrated that triploid and diploid trout had similar day-night distribution patterns, but triploid trout exhibited a lower emigration rate from the lake and lower catch rates in some lakes. Overall, triploid rainbow trout represent a viable alternative to stocking of diploids, especially in lakes draining to rivers, because they are sterile, have comparable home ranges, and less often migrate.