Mitigation research update Sample Clauses
Mitigation research update. Agenda Item 1 focused on information sharing and included presentations highlighting initiatives specific to seabird conservation in pelagic longline fisheries. Brief summaries of presentations are included below. SBWG-4 Doc 05 presented the preliminary findings of two line-weighing trials in the Australian tuna fishery. The trials examined the effects of seabird-friendly (fast sinking) branch lines on catch rates of target and non-target fish. In the event that no effects were detected the effectiveness in deterring seabirds would then be assessed. There was no statistical difference in the catch rates of Yellowfin tuna on gear configured with 60-g weights at 3.5 m from hooks (the industry standard) and gear with 120-g weights 2 m from hooks. Further, there was no statistically detectable difference between gear types in catch rates of other commercial species combined (Bigeye tuna, Albacore tuna, Dolphin fish and Broad- billed swordfish). It must be noted, however, that the catch data were highly variable and derived from a sample size of only 30 sets of the longline (36,000 hooks). Similarly, there were no statistical differences in the catch rates of Yellowfin tuna between branch lines with 60-g weights at 3.5 m and those with 40-g lead weights placed at the hook (hook-leads). There was also no detectable effect of the hook-lead gear on dolphin fish and a range of shark species combined. There was, however, a negative effect of the hook-lead branch lines on catch rates of broad-billed swordfish. However, the total number of swordfish caught was too small to justify drawing firm conclusions about ▇▇▇▇ leads and swordfish at this stage. The hook lead trial is currently underway and will be completed in early 2012. SBWG-4 Doc 06 provided an update on the BS30 underwater bait setter designed to release baited hooks at depth in pelagic longline fisheries. In the austral winter and spring of 2011 a prototype version of the underwater setter was tested in the Uruguayan swordfish fishery against White-chinned Petrels and Black-browed Albatrosses. In 35 days of fishing in the absence of other deterrent devices, two seabirds were caught on hooks deployed underwater and 11 were caught on hooks deployed at the surface. This result, although reasonable for a prototype underwater setter, fell short of the established standard, which is to eliminate or reduce to negligible levels mortality of deep diving species such as White- chinned Petrels. The prototype was sensi...
Mitigation research update. The Working Group welcomed recent improvements identified by BirdLife’s Albatross Task Force in Argentina with the use of bird-scaring lines in the industrial demersal trawl fishery, particularly the testing of an off-setting towed device, which improved the performance of bird-scaring lines, significantly reducing the incidence of cross-over between bird-scaring lines and warp cables (SBWG-4 Doc 13). It was noted that results from these trials will be considered for inclusion in the Argentinean National Plan of Action - Seabirds. SBWG- 4 Doc 13 also reviews progress in the demersal ▇▇▇▇ trawl fishery in Namibia where the use of bird-scaring lines has significantly reduced seabird interactions with trawl warp cables. Modelling highlighted that the most important factors related to seabird interactions were offal discard, use of a bird-scaring line and season in this fishery. As a result, mitigation requirements have been included in the Namibian ▇▇▇▇ Management Plan and Namibia’s draft National Plan of Action – Seabirds (NPOA – Seabirds). SBWG-4 Doc 55 provides a review of seabird mitigation research and management in the Falkland Islands/Islas Malvinas1. The paper highlights data gaps within observer data and stresses the need for finding a statistically rigorous proxy for cable strike mortality which could be used as a measure of performance with respect to setting targets in NPOA - Seabirds. To investigate this issue, experimental plans were outlined that comprise the random allocation of bird-scaring lines under differing environmental conditions with personnel in a support vessel astern of the fishing vessel, noting injured, moribund or dead birds behind the vessel in order to examine the relationship between seabird and warp cable strikes and levels of unobserved ("cryptic") mortality. The paper also outlines future work to be conducted in the fishery which includes mesh size trials to improve the selectively in the rock cod fishery and thus reduce discard levels. Argentina expressed their appreciation for the papers presented and made a statement in relation to SBWG-4 Doc 55, which they requested be annexed to the report (Annex 11). The UK asked that their position on the issue raised by Argentina be included as an annex to this report (see Annex 12). The Working Group reiterated previous advice that during trawl fishing seabirds are attracted to the vessel by the discharge of processing waste. All previous studies on this topic have shown that when...
Mitigation research update. A major product of previous SBWG meetings has been a review of information on current mitigation research for pelagic long-line fisheries and the identification of knowledge gaps (AC3 Doc 14 Rev 4, Appendix 4, Table 2; AC4 Doc 14 Rev 4, Annex 5; AC5 Doc 14 Rev 1, Annex 3). The advice embodied in the table has been distributed to some of the tuna Regional Fishery Management Organisations (tRFMOs), where it has been well received. At this year’s meeting the Working Group reviewed and updated the information in this table, following presentation of the papers referred to in Section 1.1 of this Report. The format of the review table was discussed by the Working Group, and it was suggested that the current format of the table does not represent the most efficient presentation of the information. It was agreed that the review information for all fishery types should rather be presented in a more narrative style, clearly stating whether the mitigation measure has proven to be effective and thus recommended as a primary measure. The results of this review in the revised format are attached as Annex 2. The best-practice advice derived from the review was once again synthesised into an advice statement that can be readily transmitted to target audiences (tRFMOs and Party’s fisheries managers). This advice is provided at Annex 3. As before, it is recommended that the Advisory Committee endorse this advice and encourage Parties to use this information to guide the development of policy and practice within the fisheries under their jurisdiction.