LE3 .A278 2021

2021

Avery, Trevor

Acadia University

Master of Science

Masters

Biology

Biology

The use of population dynamics in fisheries management is a crucial tool to understand trends and appoint sustainable harvest rates. In the Bay of Fundy (BoF), Striped Bass Morone saxatilis is a highly prized recreational fishery and aboriginal FSC fish. Striped Bass are found throughout Minas Basin, where they are believed to mix with U.S.A. Striped Bass populations. Mixing of these populations creates difficulties in determining population structure which is required for implementation of effective conservation actions for Canadian stocks. Here we use catch data from 1981–2019, as well as mark-recapture to answer information gaps on population structure. Specifically, we address information gaps on movement, length frequency, weight-length relationships, and estimating growth using tag data. Our data suggests that 99.5% of bass tagged over 7 years did not leave the Minas Basin. Growth models were comparable to traditional length-at-age models with Francis and Wang models outperforming Fabens models. 183 tissue samples were analyzed using next generation sequencing (NGS), single nucleotide polymorphisms (SNP)s and microsatellites and summary of mark-recapture studies since the 1930s to determine the presence and abundance of other populations in the Minas Basin, and genetic origin of bass in Labrador and Annapolis River. Of the bass chosen for higher probability of migrancyanalyzed using SNPs ,99% were of Shubenacadie River origin, with one U.S.A. migrant, and no hybridization detected. Proportions in Annapolis River were 2.4% for both Saint John River and U.S.A. origin and 95.2% Shubenacadie River origin. Labrador bass (n=8) were of Miramichi River origin, which is the first genetic evidence of Striped Bass expanding past its native northern range. Across the entire Atlantic coast into the BoF 48 (0.002%) transboundary recaptures have occurred from published studies using over two million external tags. These results indicate that U.S.A. migrants present in the Minas Basin are insignificant and the adjustment necessary for the Shubenacadie River population would be negligible.

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https://scholar.acadiau.ca/islandora/object/theses:3644