The task to estimate the escape mortality of krill during the fishing operation assigned by Scientific Committee requires assessment of the total krill passed through the rope and netting parts of trawl and krill amount appeared unviable in the process of escapement. The recommendations presented are the first attempt to develop the method of instrumental assessment of the «escape mortality». Estimation of the total amount of krill escaped from the rope and netting parts of the trawl is proposed to carry out on the basis of the complex application of fine-meshed chafers and acoustic method. The method of fine-meshed chafers allows obtaining the quantitative assessment of krill killed during escapement from the trawl. However, the practical implementation of fine-meshed chafers requires special investigation on methodical and technological issues of estimating krill escape mortality. The problems and approaches to elaboration of the efficient method for «escape mortality» study by standardizing data collection and processing, including a standard chafer design, are discussed.
Abstract:
Standardization of fishing effort on the basis of the generalized linear models with mixed effect (GLMM) allows to the authors to analyze the specific character of the spatial distribution of fishery at the scale of Area 48, Subareas 48.1-48.3, SSMUs and years using CAMLR statistical database. The interannual variability of the standardized CPUE related to the fishery performance was analyzed. It was revealed that dynamics of the most important fishery index - standardized abundance index CPUE in Subareas 48.1-48.3 and SSMUs did not correspond to the dynamics of krill density and biomass distribution, obtained from CCAMLR 2000 Survey and available data of the national acoustic surveys. The performance of the fishery and attractiveness of any SSMU for fleet operation will determined by the fishable part of krill biomass rather than the total krill biomass in the area. The high variability and different trends of CPUE distribution by Subareas and SSMUs, differences between spatial-temporal distributions of CPUE and krill biomass from acoustic surveys , huge confidential intervals of annual CPUE estimates evidence that inter-annual variability of standardized abundance index of krill obtained from CAMLR statistical database cannot be used for quantitative understanding of the process of the actual krill distribution in Area 48. The long-term fishery management in Area 48 will be required new international acoustic surveys and full-scale usage of available data from the national acoustic surveys.
Abstract:
This paper describes distribution and size-age composition of Antarctic krill (Euphausia superba) in commercial catches by Russian trawler 'Maxim Starostin' in the South Orkney region (Subarea 48.2). The fishery operations were conducted between January and March in 2008/2009 and 2009/2010 seasons. All age cohorts of krill passed spawning during the season 2008/2009, while in anomalous cold 2009/2010 season significant proportion of krill of cohort 2+ skipped spawning. Individuals of Antarctic krill in age 1+ were absent in catches in both 2008/2009 and 2009/2010 seasons. Possible reasons of this phenomenon are discussed.
Abstract:
The WG-FSA Subgroup on VMEs was tasked with providing a draft template of a Report on Vulnerable Marine Ecosystems to WG-EMM and WG-FSA in 2010. This paper provides a draft template, including the workplan and discussion. It has been compiled by the Subgroup for consideration at WG-EMM in 2010. The structure aims to follow the logic of the fishery reports already provided by WG-FSA: (i) Status of the fisheries, (ii) Knowledge on the fish stocks, (iii) Methods, (iv) Assessments of status and future catch limits, (v) Other Issues, and (vi) Advice. These topics have been tailored to suit the issue of VMEs, resulting in the following structure to replicate that approach: (i) Details of Bottom Fisheries, (ii) Details of Vulnerable Marine Ecosystems, (iii) Assessments of VME Impacts, (iv) Management Strategies to conserve VMEs, and (v) Management Advice. The long lists of tasks currently before the Scientific Committee and its working groups have been embedded within this structure in order to give them a greater context than as the lists from our reports. This should help each working group prioritise the future work and identify the key methods, parameters or field strategies that need to be undertaken. Discussions to date would suggest that the report be routinely update each year in WG-FSA but with input from WG-SAM on the development of assessment and evaluation methods, and from WG-EMM on consideration of the objectives for VMEs and their ecology would occur in WG-EMM. The assessments and advice would arise from WG-FSA. It is envisaged that, following comments by WG-EMM, a draft report will be generated as far as possible for consideration by WG-FSA later in the year.
Abstract:
High densities of pterobranchs (Phylum Hemichordata: Class Pterobranchia) and sea pens (Phylum Cnidaria: Order Pennatulacea), two vulnerable marine ecosystem (VME) indicator taxa, were encountered at sites on the shelf of the eastern South Orkney Islands. The details of these encounters, utilizing occurrence and abundance in bottom trawl catches, are provided. The distributions of standardized densities for these taxa reveal at least one station location for each taxa with anomalously high levels of biomass. These two stations should be considered for designation as VMEs. This proposal is structured according to the guidelines set out in Conservation Measure 22-06 (2009), ANNEX 22-06/B.
Abstract:
An update on the citation ranking of CCAMLR Science and the online publication developments are provided. The Working Group is invited to comment on the procedures for citing and public access to working group documents and the process of document submission to working groups. All authors and reviewers are thanked for their continued support to CCAMLR Science.
Abstract:
We report results of analyses of niche occupation among mesopredators in the Ross Sea region, Antarctica, considering three important components: 1) projected distribution and overlap across the surface of the ocean, 2) capacity to utilize differing amounts of the water column (foraging depth) and 3) diet. Species included were: Antarctic Minke Whale, Ross Sea Killer Whale (ecotype C), Crabeater Seal, Weddell Seal, Emperor Penguin, Adélie Penguin, Light-mantled Sooty Albatross, and Antarctic and Snow petrel. The apex predators, Leopard Seal and Killer Whale ecotype A/B, were not included because of their rarity and, therefore, lack of adequate sighting data on which to generate spatial models. We also did not have adequate data to model Arnoux’s Beaked Whales, Antarctic Toothfish nor Colossal Squid, which likely are also important mesopredators, particularly adult toothfish. We modeled mesopredator species distributions at a 5km/pixel scale, using environmental data and species presence localities from at-sea surveys and other sources. A machine learning, “maximum entropy” modeling algorithm (Maxent) was used to model spatial patterns of species’ probabilities of occurrence, and these data were used to identify areas of importance to species in a conservation prioritization framework (Zonation). Data on depth of diving and diet were taken from the literature. Three patterns of horizontal spatial use of the Ross Sea were apparent: 1) Shelf Break: restricted mostly to the shelf break, which includes outer continental shelf and slope (Light-mantled Sooty Albatross); 2) Shelf and Slope: full use of both the shelf and the slope (Ross Sea Killer Whale, Weddell Seal); and 3) Marginal Ice Zone (MIZ; pack ice surrounding the Ross Sea post-polynya): combinations in which the slope is the main habitat but western and eastern portions of the shelf (where sea ice is persistent) are used as well (Minke whale, Crabeater Seal, penguins, petrels). Diet composition overlapped extensively, but use of foraging space was well partitioned by depth of diving. Horizontally, the entire suite of mesopredators used the entire shelf and slope in a mosaic pattern although, not necessarily during the same season. Spatial modeling of species richness, supported by Zonation analysis, indicated the outer shelf and slope, as well as deeper troughs in the Ross Sea Shelf and Ross Island vicinity to be particularly important to the upper trophic level organisms of the Ross Sea. Our results substantially improve understanding of these species’ niche occupation previously only described using heuristic approaches.
Abstract:
This report provides the scientific basis, validating the results of the CCAMLR Bioregionalization Workshop (2007) as well as the report of ASOC (2010), for identifying the Ross Sea as one of 11 areas deserving close scrutiny for inclusion in a network of marine protected areas. CCAMLR (2007) identified the Ross Sea as an area of high biodiversity on the basis of its high physical heterogeneity; ASOC (2010) compared characteristics of the Ross Sea to areas designated under various international agreements instituted to preserve biodiversity. The CCAMLR (2007) subsequently was endorsed in the joint meeting of CCAMLR's Scientific Committee and the Environmental Protocol's Committee on Environmental Protection (ATCM XXXII-CEP XII, Final Report, 2009). Considered herein is the Ross Sea shelf and slope, which is a smaller portion of the area identified in CCAMLR (2007) as “Ross Sea shelf”. Waters overlying the Ross Sea continental shelf and slope comprise ~2.0% of the Southern Ocean, an area inconsequential in size from a global perspective. However, as shown by this summary of information — amassed from the national research programs especially of Italy, New Zealand, United Kindgom (during the “heroic” era), and United States — the Ross Sea not inconsequential is its biodiversity nor its disproportionate contribution to world populations of many well-known iconic Antarctic species. The data and information presented herein show that the Ross Sea:
Abstract:
The krill escapement mortality and the methods to determine it are closely connected with the need to have systematic observer coverage in the Antarctic krill fishery. Experiments to estimate krill escapement mortality should be introduced on all krill fishing vessels that carry scientific observers onboard. To provide krill escapement mortality experiments it is proposed that data on speed of trawling are added in form C1. It is proposed to add appropriate regulations to the Scientific Observers Manual and new suitable section to the Observer Cruise Report. The need to have observers collecting data on krill escapement mortality emphasizes the need to have a comprehensive observer program in place for the Antarctic krill fishery.
Abstract:
To support the implementation of both the precautionary and ecosystem approaches to the ongoing management of the Southern Ocean krill fishery, Norway would like SC-CAMLR and its Ecosystem Monitoring and Management Working Group to consider a proposal to obtain annual krill biomass information in CCAMLR sub-area 48.2.