In this document, we revise stock status assessments of D. eleginoides in research blocks 58.4.4b_1 and 58.4.4b_2 using CPUE analogy method, Petersen method and CASAL model. Detailed results of reanalysis using CASAL models in research block 58.4.4b_1 are described in a separated document.
We reset the revised research blocs drawn along the outer margin of grids because the previous block had not contained the eastern grids accurately, and recalculated the sea bed area sizes (600-1 800 m) using the same GIS software (GEBCO_08 Grid, version 20100927) as the latest CCAMLR Statistical Bulletin.
The estimated stock size in block 58.4.4b_1 was 510, 336 and 333 tonnes in CPUE analogy method, Petersen method and CASAL OB_1b model (vulnerable biomass in 2014), respectively.
The stock sizes of D. eleginoides in block 58.4.4b_2 is estimated at 654 tonnes only by using CPUE method, as the catch and tagging data in block 58.4.4b_2 was not enough to be applied to Petersen method and CASAL models.
We propose to continue the current research operation for the next fishing season with the same survey design and total sample size of 60 tonnes in order to further strengthen the stock assessments in the area.
Abstract:
The current season (2014/15) is the final one of the first three-season research which began in 2013 in data-poor fisheries. In the present report, the next three-season (2016-18) research plan in Division 58.4.3a was revised using the latest CCAMLR C2 and Observer data.
The stock sizes for block 58.4.3a_1 was estimated by the Petersen estimator and the CPUE x seabed analogy method.
The stock size using the Petersen estimator was largely different from that using the CPUE method. Predicted numbers of tag recaptures from the estimated stock sizes using the Petersen method were generally consistent with the observed number during 2013-14 seasons, but those using the CPUE method were inconsistent.
We also made analysis on spawning dynamics for D. eleginoides in Division 58.4.3a and compared to the results in other regions in the Southern Indian Ocean. The stock seems to be self-sustainable because of the existence of fish with advanced gonadal indices in the slope area and recruitment of small sized fish mainly in the shallow area, although the stock has a possibility of metapopulation throughout the Southern Indian Ocean as previous genetic studies indicated.
Understanding of the resource structure through clarification of their life history is essential to establish stock assessment and robust stock/ fisheries management of Dissostichus spp. population(s) in data- poor exploratory fisheries. During the second three-season research, we will continue enhanced tagging program, and collection and analysis of biological data including otoliths and gonads to clarify migration route and associated life stages of the fish.
To this end, we propose to follow the current research style in the current research blocks for the second three-season research with the sample sizes estimated following the procedure recommended at the WG-FSA in 2013 in order to maximize the expectation of tag-recapture to the extent possible under the precautionary exploitation rate.
Abstract:
The current season (2014/15) is the final one of the first three-season research which began in 2013 in data-poor fisheries. In the present report, the next three-season (2016-18) research plan in Division 58.4.2 was revised using the updated CCAMLR C2 and Observer data.
The stock sizes for a research block (58.4.2_1) were estimated by the Petersen estimator and the CPUE x seabed analogy method using updated CCAMLR C2 data and reference area sizes.
Understanding of the resource structure through clarification of their life history is essential to establish stock assessment and robust stock/ fisheries management of Dissostichus spp. population(s) in data- poor exploratory fisheries. During the second three-season research, we will continue enhanced tagging program, and collection and analysis of biological data including otoliths and gonads to clarify migration route and associated life stages of the fish.
To this end, we propose to follow the current research style in the current research blocks for the second three-season research with the sample sizes estimated following the procedure recommended at the WG-FSA in 2013 in order to maximize the expectation of tag-recapture to the extent possible under the precautionary exploitation rate.
Abstract:
The current season (2014/15) is the final one of the first three-season research which began in 2013 in data-poor fisheries. In the present report, the next three-season (2016-18) research plan in Division 58.4.1 was revised using the updated CCAMLR C2 and Observer data.
The stock sizes for five research blocks (58.4.1_1, 58.4.1_2, 58.4.1_3, 58.4.1_4 and 58.4.1_5) were estimated by the Petersen estimator and the CPUE x seabed analogy method.
Understanding of the resource structure through clarification of their life history is essential to establish stock assessment and robust stock/ fisheries management of Dissostichus spp. population(s) in data- poor exploratory fisheries. During the second three-season research, we will continue enhanced tagging program, and collection and analysis of biological data including otoliths and gonads to clarify migration route and associated life stages of the fish.
To this end, we propose to follow the current research style in the current research blocks for the second three-season research with the sample sizes estimated following the procedure recommended at the WG-FSA in 2013 in order to maximize the expectation of tag-recapture to the extent possible under the precautionary exploitation rate.
Abstract:
In 2014, the Scientific Committee endorsed a proposal from South Africa that the Secretariat be tasked with developing a proposal for funding support from the Global Environment Facility to build capacity among GEF-eligible CCAMLR Member countries to strengthen their participation in CCAMLR (SC-CAMLR-XXXIII, paragraph 10.30). This report updates progress report 1 presented to WG-EMM-15 (WG-EMM-15/15 Rev. 1 – revised text highlighted).
Abstract:
This paper describes the following elements associated with the proposal for a Marine Protected Area in the Ross Sea Region (CCAMLR-XXXIV-29):
a possible procedure for reporting on research and monitoring activities within the proposed Ross Sea Region Marine Protected Area (RSRMPA);
how the Commission might review the extent to which the objectives of the RSRMPA are still relevant and are being achieved; and
the period of designation for the RSRMPA.
There is no abstract available for this document.
Abstract:
Loss of sea-ice, ice shelves and retreat of coastal glaciers around the Antarctic Peninsula in the last few years has exposed new open water, allowing large blooms of phytoplankton to flourish in the newly exposed coastal areas. This new productivity has important consequences as the phytoplankton die and sink to the sea-bed where the carbon is sequestered for thousands of years. This carbon sink acts as a negative feedback to climate change, with an estimated 2.9 million tonnes of carbon drawdown per year on the West Antarctic continental shelf.
Carbon accumulation differs significantly between regions based on specimens collected from the continental shelves of South Georgia, the South Orkney Islands and Bellingshausen, Amundsen and Weddell Seas. The South Orkney Islands are the most productive region per km2 but, at only 4x104 km2, the greatest overall gains are for the larger continental shelves.
There is no abstract available for this document.
Abstract:
The program Integrating Climate and Ecosystem Dynamics, which is a partner program of IMBER and SCAR, will be holding a conference on assessing status and trends of habitats, key species and ecosystems in the Southern Ocean in April 2018. This background paper is an invitation to Members of the SC-CAMLR to participate in working groups on four themes that will be of benefit to SC-CAMLR: (1) Assessments of status and trends in habitats, species and ecosystems, and the causes of change (attribution); (2) Responses of species to changing habitats, including ocean acidification, sea ice and temperature; (3) Modelling and analytical methods to assess status and trends; and (4) Implementation of observing systems to estimate dynamics and change. These themes aim to facilitate contributions of the Antarctic and Southern Ocean marine science community to: the next assessment by the IPCC and recent initiatives to assess status and trends in global ocean ecosystems; the Southern Ocean Observing System; the SCAR Report on Antarctic Climate Change and the Environment; CEP; SC-CAMLR; and IWC-SC.
