Anthony Smith (Consultant)Key Words:
Stock status; Status of Australian Fish Stocks, SAFS; Undefined; Negligible; ConfidenceSummary:
The Status of Australian Fish Stocks (SAFS) reports are relatively new reports which, for the first time in Australian fisheries management, brings together the best available biological, catch and effort information to determine the status of Australia’s wild catch fish stocks against a nationally agreed reporting framework. The FRDC National Priority 1 targets of the FRDC Research, Development and Extension plan 2015-20 include two elements relevant to the undefined category in this nationally agreed reporting framework. The first is to increase the number of species covered in SAFS to 200 by 2020. The second is to reduce the percentage of species classified as undefined to less than 10 per cent by 2020. Given that a greater proportion of the additional species to be introduced are likely to be data-limited, since major stocks by value are already included in SAFS, meeting these two targets simultaneously by 2020 poses some challenges.
To address this issue, a project was funded to: (i) Develop and assign categories for the "undefined" classification in SAFS; (ii) Provide improved description of and guidance for the "undefined" classification in SAFS; and (iii) Review how "negligible" catch is addressed in SAFS and provide clear description and Guidance.
The authors reviewed the Undefined and Negligible stocks in the SAFS report. Of the 49 undefined stocks, 19 were potentially assessable, 22 stood as undefined, and 8 could potentially be classified as Negligible catch (Table 2). The number judged potentially assessable may be somewhat inflated, because the authors considered that Murray Cod was assessable, but should be assessed as a single stock (consistent with the text on stock structure in the SAFS report), rather than as 5 separate stocks divided by state and territory. If the authors’ judgement about stock structure for Murray Cod was to be accepted, then the total number of undefined stocks would be 45, with 15 potentially assessable, 8 negligible, and 22 undefined. Very few of the reports for the undefined stocks explain whether either fishing mortality (F) or biomass (B) could be assessed. Most reports just point to problems with the data or information and then state that this results in an inability to assess and therefore an undefined classification. The authors used their expert judgement, based on a reading of each report, to judge whether the stock was classified as undefined because F could not be estimated, B could not be estimated, or both. Based on this judgement, they found that 27 were undefined for both F and B, 16 undefined for B, but could possibly be defined for F, and 6 were undefined for F, but could possibly be defined for B. The authors provide added descriptions and guidance for the undefined classification in SAFS, including some discussion on the wording of what constitutes confidence in an assessment. The authors agree with all 19 of the Negligible stock classification, but provide some commentary on why they propose that the “cross-jurisdictional” component of the Negligible catch definition in the proforma should be either deleted or demoted to optional.
This report was compiled for the SAFS Advisory Group to inform the SAFS classification framework and help progress discussion in relation to moving forward to reduce the number of undefined stocks in SAFS as more data-limited species are incorporated over time. These findings will be presented at the May 2017 SASF Advisory Group meeting.