Investigating the genomics underlying fish movement and behaviour

• Main Author: Thorstensen, Matthew John
• Other Authors: Jeffries, Kenneth (Biological Sciences), Garroway, Colin (Biological Sciences), Treberg, Jason (Biological Sciences), Muthukumarana, Saman (Statistics), Rogers, Sean (University of Calgary, Biological Sciences)
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2021
• Subjects: ecology; walleye; metabolites; freshwater; population genetics; RNA; DNA; bioinformatics; conservation; Canada; Fish Lake; First Nations
• Online Access: http://hdl.handle.net/1993/35906

Movement of organisms through space has large effects on population dynamics, reproduction, and persistence. Movement of genetic material can sway the evolution of populations by influencing local adaptation and population structure. Therefore, information on movement is of fundamental and conservation importance for wild organisms, including freshwater fishes that are especially vulnerable to environmental change. Movement has been connected to environmental, physiological, and genomic factors in fish, although most research has focused on anadromous species. Walleye (Sander vitreus) is an economically and culturally important obligate freshwater fish with a native range across North America, in which movement is relatively less well-understood than in anadromous fish. Lake Winnipeg walleye are the largest component of the second-largest freshwater commercial fishery in Canada, contribute to a large recreational fishery, and provide subsistence for First Nations communities around the lake. To provide a genomic context for movement studies, Lake Winnipeg walleye population structure was established using genomic variants from RNA, where a metapopulation characterized by basin-specific subpopulations was found. Gene flow was found to likely move from south to north in the lake. Gene flow between nearby Lake Manitoba and Lake Winnipeg was found to be slightly stronger going into Lake Winnipeg, but low overall (approximately 0.0027 fish per year) and only started between 550 and 1,219 years ago. Signatures of protein degradation were higher in north basin walleye of Lake Winnipeg, consistent with a possibly longer travel distance needed for those fish to reach spawning areas. Movement within Lake Winnipeg walleye was studied in the context of maximum residency, where fish that stayed in any one ecological zone were given a 1.0 residency value. Fish that spent an even proportion of time among three ecological zones (south basin, narrows, north basin) were given a 0.3"3" ̅ residency value. No genomic variants were ...