CCAMLR

In agreement with the Report of the IXX WG-EMM (Art. 2.78; p.128), the current paper presents the next Italian survey, that will be carried out in the Ross Sea during the austral summer 2003-2004. The research consists of three core activities: (1) Acoustic sampling on krill (E. superba and E. crystallorophias) populations and concurrent censuses of their top predators for estimating krill distribution and abundance, and the effects of predators on altering them; (2) Net sampling for describing krill demography, energetic/physiology and genetics; (3) CTD and XBT sampling for identifying the characteristics of the water masses which influence krill ecological behaviour. All these activities will be undertaken synoptically along a cruise track (about 2500 nm) that gives an uniform density of acoustic, net and CTD samplings across the whole area (90000 nm2). The primary objective of the research is to improve those measurements required for the conservation of krill biology in the Ross Sea and the adjacent area of the Pacific Ocean. The second main objective is to use krill as model organisms for studying the interactions between environment and organism variability. The third main objective is to investigate the relationships between krill (E. superba) and their main competitive or predator species.

Results from an acoustic krill survey in the Elephant Island Area carried out Jan 27th to Feb 4th 2001 are presented. Data were collected with a SIMRAD EK60 Scientific Echo Sounder installed on the R/V “Polarstern”. The collected acoustic data were post-stratified in three strata based on demographic results obtained by net sampling. Data files from the 38 kHz and 120 kHz recordings were prepared and processed according to protocols used for the CCAMLR 2000 Synoptic Survey. An average biomass density of 15.32 g/m2 and a standing stock (B0) of 1.7 million tonnes were estimated for the entire area. The highest density was found in the southernmost stratum and lowest density in the northernmost stratum. The estimated average agrees well with estimates made by the U.S. AMLR program from two surveys (15.6 g/m2 and 12.8 g/m2 respectively) performed the same field season in partly the same area, and with the estimate based on RMT-8 net sampling carried out during the “Polarstern “ expedition (13.04 g/m2). The biomass density presented here is also higher than the long-term running mean from net samples for the Elephant Island area (13.9 g/m2, 1977- 2001).

This document lists up the current form to be filled in the observer manual for the krill fishery. I raise the underlying problem to be clarified or modified. This includes technical problems, workload limit, and also the problem of the commercial confidentiality. The current manual consists of nine forms and some of them were developed independent from other forms. Once the observer at sea tries to follow the manual as a whole, many conflicts arise. This document points out that the necessary revision must be undertaken by simulating the observer’s work onboard as a package of krill observer form, so that it would be reformed as a user friendly manual

Log book data from Japanese Krill Trawlers were used to characterize their fishing strategies, especially focusing on their movement in time and space. The operations were grouped into ‘operation units’ which consists from a group of repeated operations within certain searching ranges (10nm, 30nm, and 60nm). Distribution of the operation units showed considerable variation in space and time.
CPUE based on 10 x 10 squares were also examined. CPUE by shots and towing time did not show good match with the plots of aggregated catch, suggesting these two kinds of CPUEs may not be good indices for expressing the status of krill in the fishing ground. Catch per fishing days maybe the reasonable index for expressing the status of krill in the fishing ground.

CPUE values of the Soviet krill fishery in 1977-1992 in subareas 48.1, 48.2 and 48.3 are standardized by vessel types, regional fishery associations, months, years and subareas. The causes which determine CPUE variability are revealed.

The paper describes moves towards accounting for the food requirements of some of southern Africa’s seabirds in management of pelagic fish stocks. It also considers moves towards establishing target populations for seabirds in South Africa, especially those of conservation concern. It describes anomalous breeding by several species of seabird at Marion Island in 1997. These are assumed to have resulted from an environmental anomaly that may have been related to the strong ENSO of 1997/98.

The development of the krill fishery can be monitored and predicted using a number of different sources of information. Information on current catches and scientific information on the krill stocks is of limited value in plotting trends in the fishery at its current level. Predictions by Members of their future plans are also of limited use because they ultimately depend on the underlying economics of the fishery. We have analysed predictions made by Members of their future activities and have found that they are generally less accurate than will be necessary to detect trends in the future. Economic information on the krill fishery has been difficult to access in the past but will be necessary to provide reliable predictions of future harvesting trends. Sources of such information are now available but the interpretation of economic and marketing information requires specialised skills which are not generally available in the Scientific Committee. Technological information may provide early warnings of developments that could later herald an expansion in krill fishing. Information on new products from the krill fishery, and new krill processing technology is widely available once patents have been lodged. We have examined patent databases to find information on products and processes involving krill and have found 376 recorded patents. These patents reveal some trends in the development of products using krill. Complete interpretation of technological and market data requires specialist skills which would have to be harnessed if full use is to be made of these sources of information. An expansion in krill fishing to relatively high levels may occur over a short (

The Fourth World Fisheries Congress will be held in Vancouver, Canada 2-6 May 2004, with the theme “Reconciling Fisheries with Conservation” (See www.worldfisheries2004.org). There is an opportunity for CCAMLR scientists to participate in a session focussing on the Antarctic. It is proposed that CCAMLR might wish to nominate co-leaders for this session and that CCAMLR should publicise the existence of this session and venue as an important opportunity to present CCAMLR science in a global context.

1. Estimating food consumption is central to defining the ecological role of marine predators. This study developed an algorithm for synthesizing information about physiology, metabolism, growth, diet, life history and the activity budgets of marine predators to estimate population energy requirements and food consumption.
2. Two species of marine predators (Antarctic fur seal Arctocephalus gazella and macaroni penguin Eudyptes chrsolophus ) that feed on krill in the Southern Ocean were used as examples to test the algorithm. A sensitivity analysis showed that estimates of prey consumed were most sensitive to uncertainty in some demographic variables, particularly the annual survival rate and total offspring production. Uncertainty in the measurement of metabolic rate led to a positive bias in the mean amount of food consumed. Uncertainty in most other variables had little influence on the estimated food consumed.
3. Assuming a diet mainly of krill Euphausia superba , annual food consumption by Antarctic fur seals and macaroni penguins at the island of South Georgia was 3•84 [coefficient of variation (CV) = 0?11] and 8?08 (CV = 0•23) million tonnes, respectively. This was equivalent to a total annual carbon consumption of 0?35 (CV = 0?11) and 0?72 (CV = 0?23) G tonnes year –1 . Carbon expired as CO 2 was 0?26 (CV = 0?06) and 0?65 (CV = 0?19) G tonnes year –1 for fur seals and macaroni penguins, respectively. The per capita food consumption varied depending upon sex and age but, overall, this was 1?7 (CV = 0?22) tonnes year –1 for Antarctic fur seals and 0?45 (CV = 0?22) tonnes year –1 for macaroni penguins.
4. The algorithm showed that the seasonal demand for food peaked in both species in the second half of the breeding season and, for macaroni penguins, there was a second peak immediately after moult. Minimum food demand occurred in both species during the first half of the breeding season.
5. As both Antarctic fur seals and macaroni penguins compete for krill with a commercial fishery, these results provide an insight into the seasons and stages of the life cycle in which competition is likely to be greatest.