CCAMLR

Analysis of VME data collected in 2008/09 by UK vessels and national and international observers onboard was carried out to explore evidence of VMEs in the Ross Sea. 2008/09 data corroborated areas in 88.1I, E and F identified in our previous analysis of data collected by observers on UK vessels between 2005 and 2007 on benthic taxa recovered from longlines. A new area was identified within 88.1K, not previously detected. A second objective was to determine whether a relationship could be established between VME Indicator Units and CPUE data collected in 2008/09, in order to understand better the meaning of our historical CPUE data. Although a positive (exponential) association was apparent between VME Indicator Units and CPUE (bits/1000 hooks), there were insufficient data at high levels of VME Indicator Units (corresponding with the levels at which notifications to the Secretariat were triggered) to determine a meaningful relationship beyond a suggestion that 5 VME Indicator units was approximately equivalent, on average, to 25 bits/1000 hooks. As expected, heavy large taxa (e.g. gorgonians) triggered 5 VME Indicator Units at lower CPUEs than 25 bits/1000 hooks, and small lighter taxa (e.g. hydrocorals) triggered VME Indicator Units at higher CPUEs. Accounting for different benthic taxa might improve the application of the VME Indicator Units as a means of highlighting potential VME risk areas.

Dense coral-sponge communities on the upper continental slope off George V Land have been identified as a Vulnerable Marine Ecosystem in the Antarctic. The challenge is now to understand their likely distribution. The CEAMARC survey of 2007/2008 found these communities at sites on the upper slope in depths of 570 – 950 m. Based on these results we propose some working hypotheses to explain their distribution. Icebergs scour to 500 m in this region and the lack of such disturbance is probably a factor allowing growth of rich benthic ecosystems. In addition, the richest communities are found in the heads of canyons. We suggest two possible oceanographic mechanisms linking abundant filter feeder communities and canyon heads. The canyons in which they occur receive descending plumes of Antarctic Bottom Water formed on the George V shelf and these water masses could entrain abundant food for the benthos. Maps of water properties measured during the Collaborative East Antarctic Marine Census (CEAMARC) survey provide some support for this idea. Another possibility is that the canyons harbouring rich benthos are those that cut the shelf break. Such canyons are known sites of high productivity in other areas because of a number of oceanographic factors, including strong current flow and increased mixing, and the abrupt, complex topography. These hypotheses provide a framework for the identification of areas where there is a higher likelihood of encountering these Vulnerable Marine Ecosystems.

The present paper describes trawl systems, discharges and systems for obtaining green weight of krill onboard the three Norwegian krill fishing vessels, Saga Sea, Juvel and Thorshøvdi

Illegal, unregulated and unreported (IUU) fishing vessels are increasingly using gillnets as a fishing method to target toothfish in the Convention area. Estimating the impact of IUU fishing is hampered by a lack of data on the design, deployment, catch and bycatch rates of gill nets. This paper describes a gillnet found abandoned by Australian vessel patrolling BANZARE Bank (Statistical Division 58.4.3b), and the toothfish and bycatch found when a section of the gillnet was retrieved. Based on the amount of toothfish found in the 8 km long section of net retrieved, upwards of 29 tonnes of intact toothfish may be removed by a single vessel’s deployment of a 130 km long series of gillnets. However these figures are likely to be underestimates of total mortality in gillnets, due to the evidence of large numbers of sea-lice depredated fish in the net.

A brief description of New Zealand scientific observer efforts in the CCAMLR Area is provided. The nature and extent of observer deployments in the CCAMLR Area are briefly described (c. 500 sea days p.a. in three Subareas). The general training of observers through to post-voyage debriefing is noted, along with details of the at-sea work conducted. Data collected and data checking approaches are briefly identified. Current and near future developments are described, noting a move toward electronic data capture at sea and improvements to VME sampling.

Conservation Measure 22-07 (2008) requires vessels fishing in the Ross Sea region (and most areas south of 60 °S) to monitor longline bycatch for VME indicator organisms. Observers classified invertebrate bycatch using new protocols and a new VME taxa classification guide, and retained these samples for subsequent onshore classification by taxonomists. Comparison of the observer’s classification versus the taxonomist’s classification showed that for most groups, the observer classifications were reasonably accurate. Classification of two groups requires further development of training materials; stylasterids and gorgonians. Errors in other groups indicated the observers did not always record all the VME taxa retained as samples, as some live on other taxa (e.g. Anemones on stylasterids). Relatively large differences between vessels in how VME taxa bycatch were recorded are noted, along with suggested improvements. Observers very rarely classified non-VME taxa as VME taxa. Some errors and confusion in terminology in how data were recorded in logbooks were noted and alternatives described. Updates to the VME taxa classification guide, and specific observer training, should permit a robust dataset on the taxonomic composition and distribution of VME taxa in the Ross Sea region and elsewhere in the CCAMLR Area.

The aim of this document is to serve as an objective guideline to decide on an appropriate observer coverage to understand overall behaviour and impact of the fishery. CCAMLR Observer data, together with haul-by-haul fine-scale data were used to identify the target SSMUs and the critical periods as baseline to evaluate the level of observer coverage needed to achieve the CCAMLR objectives. The analysis revealed that the key to a successful observer program is 100% participation by all Members in providing systematic observer coverage, with 100% vessel time coverage to ensure viable data collection. An urgent need for capacity building by all fishing nations is re-iterated so that a large number of qualified observers are able to be deployed for 100% vessel time to ensure acquisition of data.