File(s) under permanent embargo
Capture-induced physiological stress and postrelease mortality for southern bluefin tuna (Thunnus maccoyii) from a recreational fishery
journal contribution
posted on 2023-05-18, 21:57 authored by Sean TraceySean Tracey, Klaas HartmannKlaas Hartmann, Melanie Leef, Jaime McAllisterJaime McAllisterSouthern bluefin tuna (SBT; Thunnus maccoyii) are a popular component of the recreational large pelagic game fishery in Australia. The fishery is managed using individual fisher catch limits. Fifty-nine pop-up archival transmitting (PAT) tags were attached to individual SBT to estimate postrelease survival (PRS) rates. Fish caught on lures configured with J-hooks (n = 44) and those caught on circle hooks (n = 8) had similar PRS rates and were combined to increase sample size, revealing a PRS estimate of 83.0% (95% CI: 75.9%–90.7%, n = 54). The PRS estimate of fish caught on lures with treble hooks was much lower, 60% (95% CI: 20%–100%, n = 5). By sampling blood from 233 fish, including 56 of the PAT-tagged individuals, we show that angling duration is related to an elevation of lactate, cortisol, and osmolarity in blood plasma, indicative of increased physiological stress. Physical damage related to hooking location, angling duration, biochemical indicators of physiological stress, and handling duration were not identified as significant factors leading to postrelease mortality. The results quantify a previously unaccounted source of mortality for SBT.
Funding
Fisheries Research & Development Corporation
History
Publication title
Canadian Journal of Fisheries and Aquatic SciencesVolume
73Issue
10Pagination
1547-1556ISSN
0706-652XDepartment/School
Institute for Marine and Antarctic StudiesPublisher
Natl Research Council CanadaPlace of publication
Research Journals, Montreal Rd, Ottawa, Canada, Ontario, K1A 0R6Rights statement
Copyright 2015 The AuthorsRepository Status
- Restricted