57 



Scientists generally will state that our level of knowledge of marine mammals 

 is very low. Tlhe only real exception to this is found in the case of the fur seal, 

 and even here our system of experimentation seems to be on the order of 

 "Let's wiggle it and see what happens". 



CJoncedvably, one or more of the marine mammals may prove to be of great 

 imx)ortance to mankind in the future. This strengthens considerably the argu- 

 ments of those who claim that greater protection should be given to sijecies 

 which are endangered, or which might conceivably become endangered. Also 

 to be considered in this context is that all of these animals are dependent uix>n 

 the oceans for their survival, and the evidence before the Committee has been 

 that the oceans are becoming more polluted, hence increasing the biological 

 stress upon all animals in it. This suggests that we should be far more conserva- 

 tive in our projections of what level of "cropfidng" or management any given 

 species can take without severe attrition. 



Barring better and more information, it would therefore appear to be wise 

 to adopt a cautious attitude towards the exploitatiion of marine mammals. 

 This approach was strongly endorsed at the recent mtemational conference 

 on the biology of whales ; one of the scientific working groups stated clearly 

 that those who wish to use a given species or i)opulation stock of animals should 

 carry the burden of demonstrating that the rate of killing will not endanger 

 that species or stock. 



Comments on PAirrictrLAE Types of Mabine Mammals 



THE WHALE (OBDEB CETACEiA) 



Whales are generally classified as belonging to one of two groups: baleen 

 whales and toothed whales. The baleen whales (as might be expected from the 

 categories) have no teeth, but instead feed on plankton and tiny animals, 

 strained through plates of baleen or whalebone which act as sieves. The baleen 

 whales tend to be larger in size, and are far scarcer than the toothed whales. 

 They have been more heavily himted and killed than most of the toothed whales, 

 some to commercial and perhaps even to biological extinction. 



Seven of the eight species of whales on the endangered list are baleen whales: 

 the blue, grey, bowhead. right, fin, sei and hximpback whales. Also members of 

 this suborder are the minke whales, which tend to be small in size, and which 

 therefore until recently have been largely ignored by the whalers. There are 

 indications, however, that hunting of minke whales is on the increase, and so it 

 may just be a question of time before these too join the others on the list of 

 endangered or extinct species. 



Scientists have expressed particular concern for the protection of the baleen 

 whales, since these are highly efficient harvesters of small ocean life which cannot 

 otherwise be effectively gathered. Thus, the reasoning goes, we would be well 

 advised to preserve these animals, if for no other reason than their ability to 

 serve as a source of food in the future. If these whales should be lost, a resource 

 of tremendous potential value would be irretrievably beyond our grasp. 



The more numerous toothed whales include many .species of porpoise, and 

 dolphins, as well as the sperm whale (the only toothed whale on the endangered 

 list). The major traditional use of the sperm whale has been for oil and sper- 

 maceti, although this use is now about to be terminated since products from 

 whales on the endangered list may no longer l)e imported in the U.S. after De- 

 cember, 1971. Few other members of the toothed whale suborder are taken 

 deliberately at this time, although the U.S. tuna fleet is known to kill as many as 

 200,000 porpoises per year in the course of the operation of its purse seine fleet, 

 and other nations may be doing the same. 



Porpoises are tied to the surface of the sea because they breathe air ; they 

 feed with tuna, and this makes it a relatively simple matter for the tuna fleet 

 to find where the tuna may be found : they just look for feeding porpoises and 

 draw their seines around the feeding activity. Some effort is reportedly made by 

 the fishermen to frighten the porpoises away by clierry bombs in the water and 

 other methods, but these are far from successful. Although porpoises can and 

 do leap above the surface of the water, when frightened they tend to dive, and 

 they run into the nets. A biologist in the National Marine Fisheries Service is 

 studying this problem, and an effort will be made to develop more information 

 on the subject in the hearings. 



NMFS also grants scientific and other permits for the taking of whales by 

 U.S. nationals. In recent years, this bureau, operating from various departments, 



