H-16 

 RESEARCH PROGRAMMES 



2.4.2 Objectives 



Because of its key position in the Antarctic ecosystem and the possibility of krill making a 

 significant contribution to world food supply at some time in the future, the studies of krill 

 proposed here have a significant part in the whole BIOMASS programme. It is planned that 

 these studies will lead to a better understanding of: (a) the fundamental biology off. superba; 

 (b) the extent of dependence of higher trophic levels on krill stocks; (c) the interrelations 

 between krill swarming and the hydrographic features of Antarctic waters. The studies have 

 been drawn up so that in addition to improving our general store of scientific knowledge, 

 sufficient information will be available before any intensive exploitation of krill begins. If these 

 objectives are successful it should be possible to make use of the large krill resource without 

 risk of lasting damage to stocks, or to stocks of mammals, birds and other animals which 

 depend to a greater or lesser extent on krill for food. 



In particular the objectives of the programme will be to: 



1 . Make an intensive study of the life history and population dynamics of krill. 



2. Elucidate the contribution of krill to the dynamics of its main predators. 



3. Develop systems to monitor changes in the abundance and composition of the krill 

 stocks. 



2.4.3 Research programmes 



It would not be possible, given the scales of the problems and the magnitude of the 

 resources that are likely to become available for the BIOMASS programme, to draw up 

 practicable proposals that would deal with all the objectives of the krill research programme in 

 the near future. The present proposals, therefore, have been selected to deal with topics that are 

 particularly important in themselves or lay the groundwork for later important investigations. 

 The specific proposals are: 



1 . Determine growth rate and longevity using (a) laboratory and field experiments, and 

 (b) collection and analysis of length composition data for krill collected in all seasons 

 and areas. 



2. Describe the spatial distribution of krill with the objectives of determining ranges of 

 biomass densities and the shape, extent and stability of swarms, especially diel 

 changes. 



3. Develop acoustic techniques for the quantitative survey and evaluation of krill stock. 



4. Carry out surveys with quantitative nets (RMT, Bongo, etc) to determine the vertical 

 and horizontal distriburion of krill in oceanic areas, coastal areas and the pack ice 

 zone. 



5. Determine the types of fishing effort data {eg, number of hauls, searching time) from 

 which a catch per unit effort could be produced to provide the most valid index of 

 abundance, and ensure that such data are collected from any commercial krill fishing 

 operations. 



6. Carry out ecological studies throughout the Southern Ocean, with particular emphasis 

 on the Weddell sector, in the most likely areas of potential intensive exploitation and 

 in the important but poorly understood area of the East Weddell Drift. 



7. Identify stocks or racial differences in all study areas. If sub-groups are discovered, 

 conservation measures and management of commercial harvesting will be expected to 

 reflect growth characteristics of such groups. 



8. Study the distributions, vertical and horizontal transport of early larvae Teees to first 

 calyptopis stage). 



