Reviewing Solutions To Reduce Unwanted Fisher Interactions With Elasmobranchs
Funder
Fisheries Research and Development Corporation
Funding Amount
$375,390.00
Summary
This project will build on the 2022 FRDC National Workshop on Shark Depredation (project number 2021-038) and have four complementary phases through: (1) a detailed review of the peer-reviewed and grey literature to identify and assess the efficacy of the most recently developed mitigation methods, (2) a survey of the scientific community and fishing-industry stakeholders (i.e. fishers, industry representatives, managers) to identify lesser known methods developed and/or used by fishers, (3) a s ....This project will build on the 2022 FRDC National Workshop on Shark Depredation (project number 2021-038) and have four complementary phases through: (1) a detailed review of the peer-reviewed and grey literature to identify and assess the efficacy of the most recently developed mitigation methods, (2) a survey of the scientific community and fishing-industry stakeholders (i.e. fishers, industry representatives, managers) to identify lesser known methods developed and/or used by fishers, (3) a series of workshops to identify the most promising approaches for mitigating depredation and plan the design of field trials, with a stop/go point occurring at the end of this phase based on whether suitable methods are found, and if so, (4) a robust experimental trial of the most promising mitigation method(s) to assess their effectiveness at reducing shark depredation. Phase 4 would be dependent on whether suitable methods can be identified through Phases 1–3. Stakeholder involvement and outreach will be a critical part of this project across all phases. The findings of this project will be widely disseminated via presentations to fishing clubs and industry members, written articles in the FRDC and fishing magazines, a final project report and subsequent peer reviewed publications. All off these outreach activities will be conducted in collaboration with the FRDC Extension Officer network. This will ensure broad adoption of the identified depredation mitigation measure(s). Objectives: 1. Review the existing peer-reviewed and grey literature to collate information on the range of methods trialled to date for reducing shark interactions with fishing and assess their relative effectiveness 2. Survey of the scientific community and fishing-industry stakeholders (i.e. fishers, industry representatives, managers) to identify lesser known methods developed and/or used by fishers which may not have been formally discussed or tested in the peer-reviewed or grey literature. 3. Conduct industry workshops to identify the most promising and practical approaches for mitigating depredation and plan a robust experimental design for future trials 4. Based on the outcomes of Objectives 1–3, conduct robust experimental trials of the most promising mitigation method(s) 5. Extend the results of the workshops and on-water testing to the wider fishing community to facilitate broad adoption of the tested mitigation method(s) (should they prove effective) Read moreRead less
Addressing Uncertainties In The Assessment And Management Of Queensland East Coast Spanish Mackerel
Funder
Fisheries Research and Development Corporation
Funding Amount
$1,026,558.00
Summary
As one of the most prominent species sold in northern Queensland fish shops, Spanish mackerel is iconic to seafood consumers as well as commercial, recreational, and charter fishers. However, a recent assessment of the Queensland East Coast stock raised significant concern about its sustainability, with a spawning biomass estimate below 20% of unfished levels (Tanimoto et al. 2021). Historical analyses indicate a substantial contraction of the spawning aggregations of Spanish mackerel in North Q ....As one of the most prominent species sold in northern Queensland fish shops, Spanish mackerel is iconic to seafood consumers as well as commercial, recreational, and charter fishers. However, a recent assessment of the Queensland East Coast stock raised significant concern about its sustainability, with a spawning biomass estimate below 20% of unfished levels (Tanimoto et al. 2021). Historical analyses indicate a substantial contraction of the spawning aggregations of Spanish mackerel in North Queensland, with those off Cairns being extirpated in the 1990s (Buckley et al. 2017). Previous stock assessments have also shown a trend of declining abundance over the last 20+ years (Welch et al. 2002, Campbell et al. 2012, O'Neill et al. 2018). This historical sustained decline, combined with the recent low biomass estimates, raise substantial uncertainty over the continued viability of the fishery.
This stock assessment result indicates the need to rebuild the stock in line with State and National policy objectives to reduce the number of overfished stocks. The high social and economic importance of Spanish mackerel in Queensland has led to significant public debate around uncertainty in the stock assessment, and the issue being debated in Queensland State Parliament.
As a result, key research gaps need to be addressed to increase the precision of future assessments and reaffirm stakeholder confidence in the stock assessment process. This project aims to address the following research gaps highlighted by the stock assessment: (1) determine the feasibility of using a CKMR method for estimating abundance of Spanish mackerel, (2) quantify cryptic mortality from shark depredation and post release survival, (3) improve catch and effort standardisation by better adjusting for potential hyperstability occurring at spawning aggregations and make the catch rate robust against potential management change, (4) assess the influence of key environmental variables on abundance and recruitment variability. This project will inform more accurate Spanish mackerel stock assessment, thereby increasing stakeholder confidence in line with Outcomes 4 and 5 of the FRDC R&D Plan (‘optimising benefits for the Australian community through fair resource sharing based on evidence-based management’ and ‘transparent decision-making tools that demonstrate best practice in fisheries management’). The project will also directly address the high priority research needs identified by the Queensland Spanish Mackerel Fishery Working Group. Objectives: 1. Determine the feasibility of a fisheries-independent CKMR-based approach to estimate absolute abundance of the Queensland East Coast Spanish mackerel stock 2. Quantify shark depredation rates (percentage of catch lost) across the fishery and provide an estimate of post-release survival 3. Improve the fisheries-dependent index of abundance through the application of Effort Signature techniques and increase its robustness to future management changes 4. Identify and quantify the effect of key environmental conditions on recruitment rates, year class strength, and abundance of Spanish mackerel in Queensland East Coast waters Read moreRead less
Development Of A Sustainable Scallop (Ylistrum Balloti) Fisheries Enhancement Program For Western Australia: Preliminary Feasibility Study
Funder
Fisheries Research and Development Corporation
Funding Amount
$920,050.00
Summary
A substantial rise in future demand for seafood is forecast with ocean fishery productivity projected to decline by up to 50% in some fisheries due to ecological disruptions. A key challenge therefore will be maintaining fishery productivity. Shark Bay and the Abrolhos Islands scallop fisheries are prime examples - following the extreme marine heat wave of 2011 lost income from these fisheries is estimated at $53 million GVP, or $155 million including multipliers.
The integration of aq ....A substantial rise in future demand for seafood is forecast with ocean fishery productivity projected to decline by up to 50% in some fisheries due to ecological disruptions. A key challenge therefore will be maintaining fishery productivity. Shark Bay and the Abrolhos Islands scallop fisheries are prime examples - following the extreme marine heat wave of 2011 lost income from these fisheries is estimated at $53 million GVP, or $155 million including multipliers.
The integration of aquaculture and wild fisheries is becoming increasingly recognised as a tool for enhancing fishery productivity (Taylor et al, 2017). Re-stocking and stock enhancement following recruitment failure could lead to faster fishery recoveries, and also be used to supplement natural recruitment to provide a more consistent and higher yield harvest from year to year. Development of supply chains for scallops into domestic and overseas high-value live markets requires consistent supply. Due to climatic variability and highly variable natural recruitment there is an urgent need to investigate scallop stock enhancement using hatchery-produced juveniles in WA.
A key element for success will be the development of reliable, efficient and scalable seed production systems, which will be based on previous research findings integrated novel, contemporary shellfish production technology. During this project, 16 million cultured scallop spat are planned to be released. The annual yield of scallops from the Rottnest SWF Zone A is 25 to 50 tonnes (whole scallop weight), or approximately 250,000 - 500,000 scallops assuming an average weight of 0.100 kg/whole scallop. This Project aims to release on average 8 million spat each year of the Project (600,000, 1,500,000 and 6,000,000 of 10mm, 5mm and 2mm spat respectively), which could contribute 45,000 hatchery-produced scallops to the catch each year assuming 2.50%, 1.00% and 0.25% of 10mm, 5mm and 2mm spat released respectively were captured, increasing yield by 8.3 – 16.6 % in the annual production, demonstrating the feasibility of scallop stock enhancement.
Objectives: 1. Develop and validate genetic tools to determine parentage / origin of scallops and measure genetic diversity 2. Develop hatchery and nursery protocols for consistent production of scallop spat 3. Develop strategies and methodologies for scallop spat deployment and stock enhancement sampling; measurement of seeded scallop spat survivorship; assessment of effect of spat size at deployment on survival rates; duration of growth to market size; determine impact of enhancement Read moreRead less
Cost-effective, Non-destructive Solutions To Developing A Pre-recruit Index For Snapper
Funder
Fisheries Research and Development Corporation
Funding Amount
$541,804.00
Summary
The population dynamics and fishable biomass of Snapper in South Australia are fundamentally driven by high inter-annual variation in recruitment, i.e. the numbers of 0+ juveniles that recruit to populations. Throughout the 2000s, SA’s Snapper stocks experienced different trends in recruitment that led to extraordinarily different trends in fishery catches. For the Spencer Gulf/West Coast Stock successive poor year classes led to the significant decline in fishable biomass, and a ‘depleted’ st ....The population dynamics and fishable biomass of Snapper in South Australia are fundamentally driven by high inter-annual variation in recruitment, i.e. the numbers of 0+ juveniles that recruit to populations. Throughout the 2000s, SA’s Snapper stocks experienced different trends in recruitment that led to extraordinarily different trends in fishery catches. For the Spencer Gulf/West Coast Stock successive poor year classes led to the significant decline in fishable biomass, and a ‘depleted’ stock status. In contrast, the Gulf St. Vincent Stock increased to unprecedented levels due to numerous strong recruitment year classes, but since 2015 has also experienced considerable declines in fishery catches. In 2019 it was classified as ‘depleting’. From 2018, concerns about both stocks prompted a comprehensive review of the fishery management approach. This resulted in significant changes to the management strategy including a spatial and long-term fishery closure. Despite this, there remains the need to monitor the stocks and demographic processes. Given the significance of variable recruitment for Snapper, the need for regional, annual estimates of recruitment as an indicator of future trends in fishable biomass has re-emerged. Between 2000 and 2010, recruitment surveys were done in Northern Spencer Gulf, for which the sampling methodology, i.e. otter trawling, was non-selective and destructive of benthic and demersal biota. One need here is to develop a cost-effective, non-destructive sampling strategy for future annual sampling. Also, there is the need to develop a better understanding of larval ecology, connectivity, and the causes of variable recruitment. Combined benefits from addressing both needs would significantly enhance predicting future trends in fishable biomass.
Objectives: 1. To develop our understanding of the processes that regulate recruitment based on finalising datasets from previous research projects that relate to the early life history, and larval and juvenile ecology of Snapper, as well as the annual variation in environmental factors 2. To undertake an empirical study to compare the utility and effectiveness of several potential sampling methodologies to provide a relative recruitment index for Snapper and to develop a sampling strategy for future surveys 3. To apply the sampling strategy as developed in Objective 2 in the following two years, to provide relative estimates of the recruitment rates for Snapper in NSG and NGSV Read moreRead less