,y4 DISCOVERY REPORTS 



the total numbers taken by the whaHng vessels in the South Shetland area. The 

 official returns, on which the latter are based, give only the grand totals taken by the 

 South Shetland fleet. The areas in which the whales were taken are not discriminated, 

 and it is thus not possible to include in these tables the total numbers taken in South 

 Shetland waters for seasons 1927-8 and onwards. 



DIRECTIONAL DATA 



In addition to recording the positions in which whales were killed, gunners of the 

 whale-catchers were asked to supply information on the directions in which Blue and 

 Fin whales were seen to be travelling, and on this subject an even larger quantity of 

 data has been collected than of that dealing with positions. 



The value of the evidence obtained in this way is not easily estimated. A trained 

 gunner can without question distinguish Blue and Fin whales accurately at a distance of 

 several miles; but to determine the direction of movement, at least to an untrained 

 observer, may be a matter of considerable difficulty. Blue and Fin whales normally 

 blow three or four times in succession, and at each blow are visible at the surface for 

 only a few seconds: they then sound and remain below water for some 10 or 15 minutes. 

 If, as often happens, several whales are in company, they will generally rise to the surface 

 and blow simultaneously. When whales are not plentiful it is possible to be reasonably 

 certain that the same school is being kept under observation; but when they are 

 abundant — and they are sometimes very abundant on Antarctic whaling grounds — the 

 difficulties are greatly increased, so much so that one feels that even gunners with life- 

 long experience may be at fault. On the other hand the whale-catchers can only visit a 

 comparatively small area in the few days they are away from the whaling station or 

 factory ship ; they will presumably become acquainted with the general trend of whale 

 movement in the area, and if this has been correctly stated in their returns the observa- 

 tions should have some value. 



As might be expected whales are not always travelling. On reaching a locality where 

 food is plentiful they will merely cruise in the neighbourhood, and it is to be imagined 

 that after a full meal they will show little activity. Large numbers of whales have been 

 entered by the gunners as not moving ; but the numbers shown as moving are usually in 

 excess and sometimes greatly in excess. 



These data on whale movement are of different quality to those which record positions 

 in which whales were killed, for the latter, though they may be rather rough approxima- 

 tions, are ascertained facts, while the former might be regarded merely as an expression 

 of the gunners' opinions. If, however, it were impossible to ascertain direction of 

 movement and the data supplied are mere guess-work, analysis of the returns should 

 demonstrate that the observations are unreliable. As explained below, resultant direc- 

 tions for each month have been worked out, and since these show some measure of 

 consistency they are included in this report. The results, none the less, show wide 

 variation and some of them present very great difficulty in interpretation. It is not 

 improbable that many of the reported movements are merely those of whales cruising 

 slowly about the whaling grounds and are thus of little significance. 



