T 



THE SOUTHERN STOCKS OF 

 WHALEBONE WHALES 



By N. A. Mackintosh, d.Sc. 

 (Text-figs. 1-9) 



INTRODUCTION 



he Discovery Committee's investigations in recent years on whales in the Southern 

 Ocean maybe considered to fall roughly into two categories. In the first place, arrange- 

 ments were made for direct observations on whales by research at whaling stations, by 

 whale marking, by records of whales seen during voyages of the Committee's ships, and 

 by the collection of additional data from miscellaneous sources. These are the type of 

 observations which can to a large extent be treated separately, and which quickly lead 

 to information of practical value on the general biology of whales. In the second place, 

 a programme of oceanographical research on very broad lines has been conducted in the 

 Southern Ocean. This is a long-range investigation designed to elucidate the factors in 

 the environment of whales which control their distribution and movements, and at the 

 same time to build up a framework of knowledge of the general hydrology and inter- 

 relations of the fauna and flora of the Southern Ocean. This work at sea, the greater part 

 of it carried out by the R.R.S. ' Discovery II ', has continued for years almost without 

 interruption, and it was impossible for the analysis of the data and preparation of reports 

 to keep pace with the rapid accumulation of material so long as work in the field was in 

 progress. Although good progress has been made with the treatment of this material, 

 some years would yet be needed for the full co-ordination of the results, and the work 

 has of course been interrupted since the outbreak of war. 



The direct work on whales, however, has reached a stage at which the results can be 

 treated comprehensively, and it is the purpose of this paper to summarize work which 

 has already been published, to present conclusions reached from additional material, to 

 correlate the results with statistics of the whaling industry, and to discuss the practical 

 implications of our knowledge of the stock of whales. This is by no means a final analysis 

 of the more direct data on whales, for it is not yet possible to complete some work on the 

 growth and age of whales (see p. 216), and the recovery of more whale marks should 

 provide further information on migrations. 



Among papers already published in the Discovery Reports frequent reference must be 

 made to Mackintosh and Wheeler (1929), Matthews (1937, 1938c) and Rayner (1940); 

 and many others contain material for consideration. In the later part of this paper con- 

 siderable use is made of the International Whaling Statistics published in Oslo by the 

 Committee appointed by the Norwegian Government, and of the important series of 

 papers by Hjort, Bergersen, Lie and Ruud on 'Pelagic Whaling in the Antarctic' pub- 



