2^ DISCOVERY REPORTS 



drift. Other, although far fewer, o-group whales marked in more easterly parts of the Weddell 

 current seem to have behaved in the same way, moving westwards into, or towards, Weddell West 

 counter to the surface stream. Moreover, whales of groups 1-4I all show latitudinal or meridional 

 dispersal that again suggests that their principal movements while feeding are against rather than 

 with the currents, the East Wind whales tending to move east, the Weddell whales west and the South 

 Georgia whales south or south-west. We cannot, of course, be sure that the apparent movements of 

 the later group whales, especially the lateral movements, are real, or even that they take place in 

 Antarctica itself, because as Brown (1954) points out, a whale may have done much travelling between 

 the positions of marking and recovery, even whales killed a few weeks after marking possibly having 

 wandered a long way off the direct lines joining the marking places and those where recovery was 

 made. Even so these resuks seem significant, especially in so far as they seem to indicate a definite 

 anti-current trending in feeding o-group whales. It must be significant, too, that the majority of 

 whales of all groups marked in the krill-poor West Wind beh have been killed farther south in the 

 well supplied feeding-grounds of the Weddell and East Wind zones, further indication of pronounced 

 trend towards regions of richer browsing. 



Definite evidence of upstream (easterly) movement in the west-going East Wind drift is scarce, 

 such indications as there are coming mainly from i, 2, 3 and 4-group whales. Brown (1956), however, 

 gives two instances involving o-group whales where easterly movement is marked, in the same paper pro- 

 ducing further evidence of due south movement in o-group whales from the krill-poor West Wind zone. 

 A particularly notable instance of upstream lateral movement in the krill-rich Weddell drift is given 

 by Ravninger (1955). A blue whale marked from the 'Enern', with two marks, one protruding, on 

 28 November 1954 in 54° 12' S, 16° 02' E, was recognised later by the captain in 60° 46' S, 

 11° 23' W on 10 February 1955. Brown (1956) records two even more striking cases where whales, 

 moving upstream, travelled a long way to the west in this krill-rich zone. A fin whale marked in 

 54°o6'S, 07°03'E on 15 November 1955 was killed loi days later in 55° 54' S, 33° 50' W, 

 1380 miles away to the west, and in the same season the mark from a blue whale shot in 59° 24' S, 

 41° 13' E on 2 November 1955 was recovered 107 days later in 61° 37' S, 08° 09' W, 1470 miles away 

 to the west. Together these records show that while feeding, or on the search for food, some whales 

 in the Weddell stream undergo a resuhant westerly movement of from 11 to 14 miles a day. 



Marks recently recovered from o-group whales in the Pacific sector, reopened, after a long interval, 

 to whaling in 1956, reveal there (Brown, 1957), a restless movement among the whales, with a distinct 

 westerly trend. This is especially noticeable in the narrow strip of West Wind water lying to the 

 south of 65° S, where some whales, both fin and blue, in the course of their summer feeding have 

 travelled almost due west for many hundreds of miles. Marks from i -group whales suggest a similar 

 movement. In this former sanctuary for whales (p. 394, Fig. 135 ; p. 410, Fig. 143) their food is scarce, 

 it being in this very region (p. 48) that they have been turning to Thysanoessa macrura to eke out it 

 seems a scanty diet. These extensive lateral summer movements, therefore, could well spring from 

 a restless search for food and are probably aggravated by the fact that large-scale dispersal to the south 

 is denied them because of the vast and impenetrable ice-sheet on the Pacific side (p. 49) that covers 

 so much of the East Wind zone. It is interesting too that so many have gone west, against, not with, 

 the surface stream. 



Finally, the marking results seem to suggest that in regions well supplied with food the whales do 



not undertake extensive lateral movements but tend to' remain where they are where the feeding 



is good. This seems to apply with particular emphasis, for instance, to Weddell West (p. 394, 



Fig. 135), a region offering a rich table for the whales and one, moreover, that even while suffering 



1 Whales into which marks have been fired and recovered from one to four years later. 



