413 



enough mesh to keep the animal from becoming entangled wherever he 

 he does become entangled, and the porpoises, as I understand it (I 

 have not been on a cruise with the tuna fishermen), typically dive 

 when they become frightened and presumably go deep into the net 

 and become entangled deep below the surface. 



Mr. AxDERSON. What happens to those that become entangled on 

 the sides where the netting is in 4-inch squares ? 



Dr. XoRRis. I imagine they drown. The question is not will the 

 present configuration work, but can you build a net in which the mesh 

 repels porposise .The problem is to place the small mesh in a proper 

 place. This, I think, is hopeful. 



Mr. Anderson. You see, this is also where the importance of the 

 number of porpoises is apparent. If we could take a certain number of 

 porpoises in a proportion to the total number of porpoises without 

 endangering them, that is one answer. If no one can tell us how many 

 porpoises there are in our oceans, it is very difficult. 



Dr. XoRRis. There has not been an opportunity to find out, really. 

 The governmental program, while working in porpoises, is very small 

 and lodged in very few individuals. They are biologists and without 

 really much in the way of resources to see, to look at the animals or 

 with the funds to develop the technology in order to make reasonable 

 counts. We need these things. 



Mr. ScHE^^LL. I asked Dr. Norris to comment on one other thing in 

 this connection. 



I have heard repeatedly that on these fishing grounds the porpoises 

 are no longer as numerous. This does not give you numbers, but it 

 seems to me this does give us a hint that the mortality is excessive if 

 the fishermen are running out of index porpoises to spot the schools 

 of tuna. 



Can you comment on that. Doctor Norris ? 



Dr. NoRRis. I have heard the same story as you have and that is 

 that the school size is reducing and that they are very much more 

 difficult to approach and to find. 



Mr. ScHEViLL. Kind of sounds like overfishing. 



Dr. Rat. The comment I would like to make is this. I think we men- 

 tion in our statement how few data we have to go on. 



I do not think anyone who has not tried it truthfully can appreciate 

 how difficult it is to count animals. Suppose we count those animals 

 that are easiest to count, namely, the fur seals that come on the 

 rookeries. 



How do we count them? We count the chiefs and multiply to get 

 the Indians. The figures are pretty good, though, but when you 

 get an animal in the open sea that only appears as a small breath of 

 steam you are really up against a terrific problem. 



We 'mentioned the fact that there are not the facilities for this 

 research. Ordinary oceanographic vessels will not work well. 



Recently, there have been developed a number of ideas, one of 

 which has been successful on the West Coast where I understand you 

 are from. 



Dr. Ray. In southern California they have some telemetry studdes 

 going on on your local porpoises, tagging with radio beacons to try 

 to find out where the animals go to identify stocks. 



