WHALE MARKING 253 



Group and Bouvet Island, a region then unvisited. Marking was also to be done around 

 the South Shetland Group, where whales had not been molested for some seasons, and 

 was to be extended into the Bellingshausen Sea as far westwards as Peter I Island, 

 a region neglected by factory ships and untouched by whaling except for operations, 

 based on the harbours on the eastern side of the sea, in the earlier days of the industry. 

 This was an ambitious programme for one season's work, but it was almost wholly 

 accomplished. Bad weather and inability to find whales north of South Georgia at the 

 outset and again later in the season in the regions towards Peter I Island caused the only 

 failures to complete the plan. This season, as far as marking was concerned, was also a 

 " Fin season " and very few of the other species were marked. 



The whales estimated as effectively marked on each of these expeditions are shown 

 in Table I, arranged according to species. They total 668 Blue, 3905 Fin, 547 Hump- 

 back, 27 Sei, 8 Right and 52 Sperm whales. 



It is useful here to explain how the numbers of whales " effectively " marked, as given 

 in this table, are calculated. These totals have been reached after a study of the log 

 books of each whale-marking cruise and after the following adjustments have been made. 

 Firstly, from the total of hits recorded there have been deducted all duplicate hits. 

 Secondly, all those marks noted as protruding are also deducted, except when such a 

 protruding mark has already been returned, for it is considered that these protruding 

 marks must usually soon be lost by the whale. To the number thus obtained there has 

 then been added the few marks recorded as misses or possible hits which have so far been 

 returned, and, finally, half the remaining "possible hits" have been considered to be 

 valid hits and added to the total. This final total is the one given in the table for the 

 numbers of whales considered to be effectively marked on each cruise, and is thought to 

 be as near as can be approached to the true figure. At the same time, with one exception, 

 these totals probably represent the maximum number of whales marked, for it is not 

 always possible to tell if a whale is marked more than once. Also, many more marks will 

 be protruding, perhaps only a very little, than those observed and noted, and the eventual 

 loss of these will further depress the true total. 



The one exception mentioned is the total for the whales marked around South 

 Georgia in the season 1934-35 : it is given as 377, but this is almost certainly too low. On 

 this cruise a deliberate attempt was made to mark every whale twice. There is no doubt 

 that this was very far from being accomplished, but, after the adjustments described 

 above had been made and after single marks returned from whales had been allowed for, 

 the number of hits recorded was halved to give the total in the table. Apart from this 

 one season the figures given in Table I for each season's results are looked upon as 

 reasonably comparable. 



The R.R.S. 'Discovery II' has carried marks and guns and, when occasion offered, 

 has marked whales. She is, however, not the type of ship able to pursue whales, and 

 any attempt to do so would interfere with her ordinary work. An occasional shot when 

 whales approach the ship is the most that can be done. 



A schematic representation of the distribution of the whales marked is given on 



