Exporatory fishing with bottom trawl conducted by the French trawler « Austral» off the Crozet archipelago (sub-area 58-6) does not allow to detect any other marine living resources than the only one Nototheniid fish Dissostichus eleginoides. The other species have no future for a commercial exploitation due to their sizes. Deep-sea fishing only (slope of the shelf :300 - 750 m) show some shoals of sub-adults and adults as observed in the division 58-5-1 (Kerguelen) located more easternly. Two geographical areas have been specially identified. Trends in yield are however not stable from one year to another and even along one fishing experiment despite a limited fishing effort. Two hypothesis are proposed to explain the trends: a quick col1apse or/and a high migratory pattern of this part of the stock. The running experiments do not allow to consider and work out a plan an high fishing effort (or in the future and even yearly fishing cruises in the sub-area.
There is no abstract available for this document.
There is no abstract available for this document.
Abstract:
This study was based on the data from the ichthyoplankton survey made in March-April 1989 by R/V "Vozrozhdenie" in the subtropical frontal zone over the South Atlantic ridge crest between 38°30’ - 45°S. and 15° - 20°W. Larvae were collected with BONGO and JUDAY nets in oblique arid vertical hauls at 500 - 0m. The method of delta-distribution of random values (Aitchison, Brown, 1957; Pennington, 1983) was used to count the larvae. The data obtained was taken to estimate the recruitment biomass (fish aged up to 1 year) in this species for the area of 87750 square miles studied. The abundance of larvae in this area was 4.3 x 10 ind., while the biomass of one year old fish obtained was 10750 tons. A whole chain of similar reproductive grounds is assumed to exist in the notal zone of the Atlantic and other sectors of the South Ocean to be able to sustain a large biomass of E. carlsbergi in waters of the south po1ar frontal zone.