DISTRIBUTION OF YOUNG STAGES OF EUPHAUSIA SUPERBA 149 



Returning northwards again it was not until the ship reached the region in which krill had pre- 

 viously been found that one individual, at St. WS 557, was again recorded in the vertical net series. 

 A small quantity of krill was taken at St. WS 560 in the i-m. net, to the westward of the north end 

 of the South Sandwich Group. 



Cape Town-Bouvet-South Georgia, October-November, 1930 (Sts. 446-472). 

 Fig. 69. 



In October 1930 the 'Discovery 11' sailed southwards on a line of stations from Cape Town to 

 Bouvet and South Georgia. The Antarctic convergence was crossed between Sts. 451 and 452. The 

 first catch of young krill was made at St. 453 where a large quantity was recorded. At Sts. 453-455, all 

 in the neighbourhood of Bouvet, a considerable quantity of krill was taken, at the last station over 

 6000. From Bouvet Island to South Georgia the track was along the edge or through the outskirts of 

 the pack-ice. Young E. superba were taken at each of the stations where the metre net was fished. 

 At St. 461 a twenty-four hours station was made, the results of which are dealt with in a separate 

 section. At St. 468 no lOO-cm. nets were fished. In his report on this series of stations Dr Kemp, 

 referring to E. superba, states: "We found krill first of all to the N.E. of Bouvet where we took a 

 quantity of adults and a great number of late larval and early post-larval forms, stages that we had 

 scarcely seen hitherto. Along the pack adults were again taken at many points and at every station 



30° 



10° 





Fig. 69. Distribution of young Euphausia superba, Cape Town, Bouvet, South Georgia 

 (i-m. net hauls), October-November 1930. 



young have been obtained, usually in great abundance. When making our way through the pack, 

 either in the main body of it or when crossing the narrow tongues, krill was almost always to be seen 

 and often it occurred in great quantity. The young stranded themselves in numbers on floes that we 

 momentarily submerged in our passage, while the adults, with greater activity, often jumped clear 

 of the water and landed kicking on ice some 10 or 12 inches above the surface. The quantity of krill 

 to be found in and near the pack at this season is amazing and the reason why whales haunt the ice- 

 edge is evident." 



South Georgia survey, November 1930 (Sts. 474-525). Fig. 70. 



After the completion of the Bouvet-South Georgia stations a plankton survey round South Georgia 

 was commenced. At the beginning of the survey, as stated by Mackintosh (1934, p. 127), the pack- 

 ice was close up to the island, but at the end of November when the survey was completed the ice 

 had receded some way to the south-east. There can be no doubt that the abundance in which young 

 krill was found in the vicinity of South Georgia during this survey was due to the proximity of the 

 pack to the island, and it is likely that earlier in this season the ice-edge extended north and west to 

 the positions shown on the map where krill was especially abundant. It is likely too that the surface 

 currents {vide Deacon, 1933, p. 183, fig. 5) would tend to transport the krill northwards and east- 

 wards in the tongue of water extending along the north-east coast of South Georgia. 



South Shetland survey, December 1930 (Sts. 537-555)- Fig. 71. 



In this survey the distribution of the young krill was much the same as that of the eggs described 

 on p. 109. The greatest concentration was at St. 537, the first on the Elephant-Joinville line: this 



