ESD risk assessment for under-utilised species to facilitate structural reform of South Australia's commercial Marine Scalefish Fishery
Investigating social acceptance for the wild catch commercial fishing industry of Southeast Queensland
eSAMarine – phase 1: the first step towards an operational now-cast/forecast ocean prediction system for Southern Australia
Isolating social and economic objectives within multiple stakeholder fisheries – a case study: the South Australian Marine Scalefish Fishery
Informing inter-jurisdictional snapper management in eastern Australia
In the recent “Status of Key Australian Fish Stocks Reports 2012” the status of snapper on the east coast was not defined because the stock was given a different status in each jurisdiction based on different assessment approaches and criteria for defining status. The need for a single, robust, consensus approach was identified as a priority in a FRDC funded national workshop on snapper held at SARDI in March 2013. In particular it was noted that, underpinning a unified approach to assessment and management, there is a need for: a better understanding of stock structure, a better understanding of the utility of fishery independent data sources, and better engagement with stakeholders. The project explicitly addresses a key Program 2 – Industry Priority identified as relevant to the FRABs in Queensland, NSW and Victoria. The systems and approaches developed as a result of this research will serve as a model in other fisheries where different jurisdictions share a common stock but lack a consistent assessment and management decision making framework.
Article
Snapper has been fished since the early development of the colony around Sydney Harbour in the late 18th century, but it was the arrival of steam power in the 1860’s that enabled fishers to start regularly targeting the abundant schools of snapper occurring in the deep-water fishing grounds outside of the sheltered bays and estuaries along the east coast of Australia. This article covers some of the history.
Project products
Developing a fishery independent estimate of biomass for snapper
Increased formalisation of harvest strategies for snapper across Australia’s four main jurisdictions (East Coast, Western Victoria, South Australia and Western Australia) was identified as a national priority (at the National Strategic Planning Workshop for Snapper Research – 1st March 2013). Two key processes were recognised as being fundamental to achieving this: 1. development of a snapper-specific integrated fishery model; and 2. integration of a fishery-independent estimate of abundance. Each jurisdiction is currently at a different level of advancement in their assessment and management capability, with WA leading the way. A snapper model is currently used to underpin the assessment of South Australia’s snapper resource, whereas Western Victoria is in the process of developing their own and the East Coast is yet to develop one. South Australia and Western Victoria are at a level where the development and integration of a DEPM, that would provide a fishery-independent estimate of biomass, would considerably enhance their respective stock assessment programs.
The need for a DEPM is more urgent for South Australia, as recent structural changes in the snapper fishery have compromised the integrity of the time series of fishery-dependent statistics that have been relied on to assess the resource in the past. Fishery-independent estimates of snapper biomass are required to feed into the existing stock assessment model to ensure that future assessments and harvest strategies are developed from unbiased information. This research direction has been unanimously supported by the relevant stakeholders in South Australia’s Snapper Fishery. The Western Victorian fishery is likely to encounter similar issues to South Australia, particularly as their fishery is dominated by the recreational sector where the routine collection of catch and effort data to integrate into the assessment process is often challenging.
Final report
This study was undertaken by the South Australia Research and Development Institute (SARDI). Through overcoming considerable technical challenges, this study was the first to successfully develop a relatively non-destructive molecular probe that can reliably identify Snapper (Chrysophrys auratus) eggs and larvae in mixed ichthyoplankton samples. This highly-specific molecular probe targets Snapper ribosomal (r)RNA and when conjugated with a reactive molecule produces a highly visible blue colour in positive reactions. Snapper eggs are subsequently easily detected using a standard stereo dissecting microscope. This novel use of an established molecular technique has re-invigorated the capability of using the daily egg production method (DEPM) to provide a fishery-independent estimate of spawning biomass for Snapper and has also increased its applicability to other species where egg identification has been problematic. This research has reduced the need to exclusively rely on fishery-dependent catch and effort data to assess Snapper fisheries and has demonstrated that the incorporation of the DEPM into South Australia’s existing assessment program is relatively cost-effective and likely to benefit the management and industry. Adding the DEPM will contribute an extra unbiased source of information that can be synthesised with existing fishery-dependent data streams that will lead to more confident assessments of the stock and ensure the long term sustainability of the State’s Snapper resource.