429 



the use of small specialized whaling vessels on which a biologist must be in 

 charge. 



Population Analyses 



It is essential that population analysis be uncoupled from the past and present 

 dependence on the capture of animals on the traditional whaling grounds. An ade- 

 quate picture of iwpulation structure can be obtained only if sampling is car- 

 ried on throughout the year in all parts of the population's range and all classes 

 in the population. To do this will require that the breeding area be found by ex- 

 ploration and that some selective whaling (under license) be done on a basis of 

 scientific rather than economic need. It will be helpful if such breeding areas 

 could be designated as research control areas where whaling would be by license 

 only. Population analyses of the sort proposed will involve the use of ships such 

 as the Peder Huse, which can serve as catchers, biological laboratories, and as 

 factory ships, and are not confined to coastal areas. This will make it possible 

 for whales taken for biological purposes to be commercially utilized. Animals 

 captured for study and subsequent processing should be subjected to at least 

 the following tests: (1) detailed analysis of reproductive state and repro- 

 ductive history; (2) age determination using teeth, ear plugs, ovarian histology, 

 jawbone structure, baleen, and biological samples prepared for later biophysical 

 and biochemical study (analysis of seasonal variations of bone tissues by an elec- 

 tron-microscope. X-ray diffraction ultra-sound, etc.) ; and (3) determination of 

 hormone levels where practical. 



Trophic Analysis for Whales 



Although knowledge of the biology of whales when they are away from the 

 main feeding grounds must be sought (see above), detailed quantitative infor- 

 mation related to energetics of whale populations must be obtained. A number 

 of topics invite attention. A few of the more obvious are listed below. 



1. Trophic effects of the removal of a major consumer, such as the blue or fin 

 whale on (a) other baleen whales and (b) other consumers of the same trophic 

 level (sea birds, pelagic seals). 



2. Seasonal and geographic localization of feeding and the role of prolonged 

 fasting. 



3. Effects of age on food habits. 



4. Role of patchiness of plankton on food searching and the local distribu- 

 tion of whales. Does patchy distribution of whale food such as krill allow un- 

 coupling of the mean productivity of a region from whale energetics? To answer 

 this would require simultaneous sampling of water and plankton at areas where 

 whales are taken and comparison of the observed productivity with average 

 values for the region. 



5. Development of models for estimating metabolic rates of large whales and 

 methods of direct measurements of metabolism on small ones. 



6. Use of aerial (and possibly satellite) photography or remote sensing to de- 

 termine patchiness and distribution of plankton. 



The patterns of distribution of the feeding of whales are widespread geo- 

 graphically while at the same time, stocks are suflBciently circumscribed geo- 

 graphically that whales should be useful monitors of pollution of the oceans 

 by heavy metals, i)esticide residue, radio nuclides, and other fallout products. 



The local distribution of whales and porpoises has already been affected by 

 the environmental deterioration associated with human activities ; their num- 

 bers in the southern parts of the North Sea have decreased markedly in recent 

 years. Since whales are among the few marine animals that can be seen from 

 above the surface of the sea and since they are at the top of the trophic pyramid, 

 it should be possible to use them as indicators of changes in the environmental 

 quality of the seas. 



Natural History of Poorly Known Species 



Work on the taxonomy and natural liistory of poorly known species should be 

 continued and expanded. The smaller cetaceans, including porpoises and dolphins, 

 in particular, invite attention. As previously indicated, they represent a biological 

 resource conce'*ning which our ignorance is almost complete. 



Study of Unexploited Stocks of Large Whales 



A few relatively unexploited stocks of large whales remain. They are too small 

 to be of major economic importance, but knowledge of them can serve as base- 

 lines with which to compare stocks which have long been exploited or over-ex- 

 ploited. The sperm whale population of the western South Atlantic and the gray 

 whale population of the eastern North Pacific offer attractive possibilities. 



