Development of resources and equipment to enable best practice in the humane dispatch of sharks caught by commercial fishers in the NT
The so called pragmatic approach to the welfare of aquatic animals (Arlinghaus et al. 2007) measures welfare status using a variety of well-established, un-controversial physiological and functional parameters (Rose et al. 2014, Browman et al. 2019). For example, all finfish, crustaceans and cephalopods can experience stress, which can lead to poor welfare outcomes (Rose et al. 2014). From an animal welfare perspective, the overall aim to maximise fish welfare during capture is to minimise stress within the constraint of practices inherent to the relevant fishing sector (Mazur and Bodsworth 2022).
Using this pragmatic approach, the Aquatic Animal Welfare Working Group (AAWWG) which was formed under the Australian Animal Welfare Strategy (AAWS, 2005-2014), developed a range of Overarching Welfare Principles which related to finfish harvested from the wild in commercial fishing industries.
Out of the eight Overarching Principles developed by the AAWWG, as pointed out by Mazur and Bodsworth (2022) the three that are most relevant to the commercial wild harvest industry are:
1. Timely handling from capture to death is essential to minimise stress;
2. Capture methods should be designed to minimise the capture of unwanted species
3. Any fish selected for harvest should be killed as rapidly as possible, by humane means suitable for the species.
To address the legislative issues under the new Act, meet current and future fish welfare challenges, and maintain their social license to fish, commercial fishers targeting sharks in the NT need to develop workable and effective standards for handling and dispatching sharks which can be recognised and prescribed under the new Regulations.
Since shark fisheries are specialist fisheries which were not covered by the AAWWG during the AAWS, there is a need to develop specific resources to assist the industry with humane dispatch of sharks.
Science shows that brain destruction by pithing or “iki-jime” is the fastest way to dispatch finfish, resulting in the lowest levels of stress and maximising the quality and shelf life of the resulting fish product (Poli et al. 2005, Diggles 2015). However, the brains of sharks are small and vary in location between species, which is why this project is being proposed and is necessary to determine the brain location of the sharks most commonly captured in the NT shark fishery, and then examine various methods of rapidly destroying the brain, in order to develop guidelines and best practice protocols for their humane dispatch. Importantly, it should be noted that this is an industry driven project.
References
Arlinghaus R, Cooke SJ, Schwab A, Cowx IG (2007). Fish welfare: A challenge to the feelings based approach, with implications for recreational fishing. Fish and Fisheries 8: 57-71.
Browman HI, Cooke SJ, Cowx IG, Derbyshire SWG, Kasumyan A, Key B, Rose JD, Schwab A, Skiftesvik AB, Stevens ED, Watson CA, Arlinghaus R (2019). Welfare of aquatic animals: where things are, where they are going, and what it means for research, aquaculture, recreational angling, and commercial fishing. ICES Journal of Marine Science 76: 82–92. doi:10.1093/icesjms/fsy067
Diggles BK (2015). Development of resources to promote best practice in the humane dispatch of finfish caught by recreational fishers. Fisheries Management and Ecology DOI: 10.1111/fme.12127
Mazur N, Bodsworth A (2022). Practicing aquatic animal welfare: Identifying and mitigating obstacles to uptake and adoption by the Australian Seafood Industry. Final Report for FRDC Project No 2019-023, March 2022. 60 pgs.
Poli BM, Parisi G, Scappini F, Zampacavallo G (2005). Fish welfare and quality as affected by presaughter and slaughter management. Aquaculture International 13: 29-49.
Rose JD, Arlinghaus R, Cooke SJ, Diggles BK, Sawynok W, Stevens ED, Wynne CD (2014). Can fish really feel pain? Fish and Fisheries 15: 97–133.
