CCAMLR

Considerable progress was made on the survey database in early 2002. However, this work had to be postponed because of a higher priority need for developing a web-based data system for the Catch Documentation Scheme. Work on the survey database in 2002 included:
• revision of the database model;
• documentation of the database specifications;
• development of data uploading routines;
• revision of data extraction routine for CMIX and trawlCI; and
• processing of historical data.
The survey database consists of some 50 tables and 50+ stored procedures and triggers. A detailed description of the database specifications is given in ‘Technical Specifications for the Survey Database (see document in ‘\FSA 2002\Survey Database’ on the server). The primary tables are: Survey; SurveyEvent; CatchSummary; CatchLWSM; and Specimen. Data from sixteen surveys have now been uploaded to the survey database.
Substantial further work is required to complete key elements of the database, as well as tidy up and transfer existing CCAMLR data to the new survey database. Future work may also include the development of a stand-alone database for at-sea entry of survey data.

The role of fish in the Antarctic food web in inshore and offshore waters is analysed taking as an example the coastal marine communities of the southern Scotia Arc (South Orkney Islands and South Shetland Islands) and the west Antarctic Peninsula. Inshore, the ecological role of demersal fish is more important than that of krill. There, demersal fish are major consumers of benthos and also feed on zooplankton (mainly krill in summer), and are links between lower and upper levels of the food web; they are common prey of other fish, birds and seals. Offshore, demersal fish depend less on benthos and feed more on zooplankton (mainly krill) and nekton, and are less accessible as prey of birds and seals. There, pelagic fish (especially lanternfish) are more abundant than inshore and play an important role in the energy flow from macrozooplankton to higher trophic levels (seabirds and seals). Through the higher fish predators, energy is transferred to land in the form of fish remains, pellets (birds), regurgitations and faeces (birds and seals). But in the wide context of the Antarctic marine ecosystem, krill (E. superba) plays the central role in the food web because it is the main food source in terms of biomass for most of the high level predators from demersal fish up to whales. This has no obvious equivalent in other marine ecosystems. In Antarctic offshore coastal and oceanic waters the greatest proportion of energy from the ecosystem is transferred to land directly through krill consumers, such as flying birds, penguins, and seals. Beside krill, the populations of fish in the Antarctic Ocean are the second most important element for higher predators, in particular the energy-rich pelagic Myctophidae in open waters and the pelagic Antarctic silver fish P. antarcticum in the high Antarctic zone. Although the occurrence of these pelagic fish inshore has been scarcely documented, their abundance in neritic waters could be higher than previously believed.

Information on the rates of incidental mortality of birds experienced by IUU vessels is extremely difficult to obtain. CCAMLR has, in the past, used data from the 1997 legitimate fishery, when a large number of birds were caught and when the implementation of mitigation measures was low, to approximate the IUU situation. This paper describes analyses undertaken using the 1997 data to refine the estimates of IUU bird catch rates for use in our analysis of the impact of IUU fishing in Subarea 48.3 (WG-FSA-02/4).

1. This paper describes a new method for estimating IUU catch of fish and birds. It utilises high quality, well-documented FPV (fisheries protection vessel) cruise data. It takes explicit account of both “seen” and “unseen” IUU fishing through a simulation model to arrive statistically rigorous estimates and confidence intervals of fish and bird catch by IUU vessels. This method has not been used previously to estimate IUU activity in CCAMLR. We recommend its continued use in Subarea 48.3 and extension to other regions of the Antarctic.
2. Of the sources of information on IUU fishing, Fishery Protection Vessel (FPV) cruises are the most consistent and reliable. The track of the FPVs on their cruises to South Georgia covers all possible areas of fishing for toothfish in Subarea 48.3. The method uses data from FPV cruises in Subarea 48.3, and the encounters between FPVs and IUU fishing activity, to estimate the total number of days of IUU fishing that could occur during each year. For each IUU incident detected by the FPV, we calculated a theoretical maximum time over which this IUU activity could have occurred. This was the time that elapsed between the FPV cruises that were immediately prior to and immediately subsequent to the incident, where these prior and subsequent cruises had not detected that same IUU activity (i.e. the same vessel). In other words, for each IUU incident we know when it was seen, and the closest adjacent times in which it was not seen – the difference being the theoretical maximum time that the vessel can have been present.
3. This theoretical maximum time was converted to actual IUU fishing time using a simulation model. For each year, the model simulated 1000 IUU fishing incidents during the year, and from the known FPV cruise pattern calculated both the observed IUU activity and the known real IUU activity. We considered IUU activity to have been observed when the IUU vessel and the FPV vessel were in the same place at the same time. When this occurred, the FPV was assumed to detect IUU activity according to an “encounter probability”. The encounter probability was estimated from the known encounters of FPV with licensed vessels. Thus for each encounter between an IUU vessel and an FPV we obtained an estimate of total IUU fishing time.
4. The total annual IUU catch of toothfish and birds was calculated using a second simulation model. Subarea 48.3 was divided into 6 Areas for the purposes of calculation of fish and bird catch associated with IUU fishing. The catch rate of fish was calculated for each Area and each year using reported catch and effort data. The catch rate of birds was calculated separately for summer and winter using previously published CCAMLR observer data obtained in the early licensed fishery (1997) when few vessels used mitigation measures. For each of 10,000 simulations fish and bird catch rates were obtained randomly from parent distributions, for each IUU-FPV incident.
5. Three years were analysed, 1998/99, 1999/00 and 2000/01. Each year covered fully the period 1 October – 30 September, thus including one summer and one winter period. The estimated total toothfish catch attributable to IUU fishing was 667 t, 1015 t and 196 t in 1998/99, 1999/00 and 2000/01 respectively (a total over the three years of 1879 t). The estimated total bird catch was 574 birds, 2200 birds and 544 birds respectively. 95% confidence limits were calculated to be 41-1778, 472-1744 and 23-481 respectively for fish and 122-1823, 825-5422 and 110-1813 respectively for birds... [Please contact the Secretariat for the full abstract.]