CCAMLR

Given Resolution 22/XXV, paragraph 3 concerning the mortality of Convention Area Seabirds to the north of the Convention Area and the request by IMAF, SC-CAMLR XXVII/15 (Para 4.3) to report these, this document provides an overview of the South African fishing sectors most likely to impact on these seabirds. A summary is provided of the recorded number of mortalities for each fishery where these data are available. All South African licenced vessels are regulated and permit conditions include regulations to minimise interaction with seabirds. There are five sectors of the South African fisheries that have the greatest potential to impact on seabirds that breed within the CCAMLR Convention Area. The demersal trawl and pelagic longline fisheries are responsible for the highest recorded mortalities of seabirds.  Independent research and measures imposed in the permit conditions for these sectors have appeared to effectively reduce catch rates from the high numbers recorded from 2004.  
The most vulnerable species to interaction in the demersal trawl fishery are Cape (Pintado) petrels, Daption capense. In the pelagic longline fishery, the highest mortality figures were recorded for White-chinned Petrel Procellaria aequinoctialis, followed by Shy Albatross Diomedea cauta.

France presented at CCAMLR XXVII an action plan aimed at reducing incidental avian mortality by 50% in the French EEZ included in the statistic division and subarea 58.5.1 and 58.6 for the period 2008/2009 to 2010/2011. The aim of this document is to present the various measures implemented and results achieved. The assessment also reports the actions taken since 2002 to reduce the incidental catch of sea birds in the area. In addition to the sharp decrease in incidental catch of seabirds in the French EEZ (see statistical report), this document presents new proposals that France would like to implement in order to pursue its efforts to minimize incidental captures.

Following the successful earlier start of the Dissostichus eleginoides fishing season in Subarea 48.3 (26th April in 2009/10 and 21st April in 2010/11) this paper summarises the results of the past two seasons and proposes moving the beginning of the fishing season to the 21st April with a further two five day extensions over the next two years to the 16th and then the 11th April.

Daylight setting is allowed in Subarea 48.4 and stringent mitigation measures have meant to date no bird mortalities have been recorded. Due to frequent storms vessels have been requesting the option to be able to set during daylight in Subarea 48.3 for safety reasons.  Recurrent cetacean presence also hampers fishing activities and the opportunity to daylight set would be beneficial as an avoidance technique. This paper proposes a 10 day trial (per vessel) of daylight setting between 1st July and 15th August (when there is the least bird activity).

In accordance with decision of SC-CCAMLR in 2010, the Russian Federation conducted research fishery on toothfish in Subarea 88.3 in the season 2010/11. The researches were carried out onboard longliner Sparta (company “Morskoi Voron”). In total, 20 trotline sets at different depths have been made, the total number of exposed hooks being 87,096. The research program covered SSRU B, C, and D of Subarea 88.3. In SSRU A longlines were not investigated because ice conditions were difficult. All toothfish catches and by-catch were subjected to biological analysis. 30 toothfish individuals of different size were tagged, size distribution of tagged fish being in accordance with the size distribution of fish of catches. Material sampled included 240 otoliths for age determination, 53 samples for genetic analysis and 42 samples for histological analysis. In total, 256 toothfish individuals were caught that corresponded to 5,230 t by weight. The detailed data on size composition, spatial and bathymetric distribution of toothfish, and its feeding in Subarea 88.3 B-D were obtained.

The Ross Sea toothfish fishery in Subarea 88.1 and 88.2A&B has been classified by CCAMLR as an exploratory fishery since 1998.  The current classification of this fishery as ‘exploratory’ has led to the widespread misconception that little information is available for this stock, and that a rigorous assessment of the stock status and estimation of long-term precautionary yield has yet to be undertaken.  In fact, many biological characteristics of D. mawsoni are now well understood, and integrated assessments using the CASAL framework have been undertaken since 2005.  Although there remain uncertainties with aspects of the stock, we propose that the stock is sufficiently well understood and assessed that it should be re-classified.  To ensure that sufficient data are acquired to continue assessment of this stock, we propose retaining several elements of the current requirements for Members wishing to participate in the Ross Sea toothfish fishery as set out in Conservation Measures 21-02 and 41-01.
 

The diet of Antarctic toothfish (Dissostichus mawsoni) and Patagonian toothfish (D. eleginoides) was examined around the south sandwich islands in the southern ocean, one of few regions with overlapping populations of the two species. Despite large differences in the proportion of stomachs containing prey (76.2 % of D. mawsoni compared to 7.2 % of D. eleginoides), diet composition was broadly similar (schoener overlap index of 74.4 % based on prey mass) with finfish (particularly macrourids and muraenolepidids) and cephalopods (mainly Kondakovia longimana) comprising more than 90 % of the prey mass of both species. Predation rates of the main fish prey, as mean counts per stomach sampled, were spatially correlated with their relative abundance around the islands derived from fishery bycatch data, suggesting a general lack of prey selectivity. This study supports the view that bathyal toothfish are opportunistic carnivores and finds that D. mawsoni and D. eleginoides occupy a similar trophic niche and are likely to compete for prey in regions where both are distributed.  However, the large increase in rate of prey occurrence and size of prey in D. mawsoni stomachs relative to D. eleginoides suggests species differences in feeding behaviour, which may reflect the increased metabolic demands of a cold water-adapted physiology.