FIBEX-An international survey in the Southern Ocean: Review and outlook

The first international experiment under the framework of the Biological Investigations of Marine Antarctic Systems and Stocks (BIOMASS) aimed at quantitative estimates of krill (Euphausia superba) in four areas of the Southern Ocean : Western Atlantic Sector, Western and Eastern Indian Ocean Sectors, two transects in the Western Pacific Sector. The method for the quantitative estimation of krill abundance by means of stratified randomized echo survey sections run by several research vessels simultaneously required a high degree of calibration and co-ordination. Catch data were needed for the interpreatation of the echo signals. Environmental data were required in order to understand the distribution and abundance of krill and of its key food organisms as well as its predators. The seagoing activities in January to March 1981 involved 12 vessels of 10 countries and produced the largest amount of data ever collected during an international co-operative study in biological oceanography. The compilation of the data sets and their transfer into a centralized computer system was the next step, carried out during an international post-FIBEX Data Workshop in September/October 1981. The Workshop produced the first estimates of krill abundance in four major areas of the Southern Ocean, also giving figures of variance. Most important for the understanding of the system will be the further combination of krill data with environmental data and other biological observations