36. Are whales found in all oceans of the world? 



Yes, whales have been observed in all oceans of the world and even 

 in fresh water. Most of the larger species continually migrate from 

 ocean to ocean with the changing seasons. 



There are two distinct species populations: the Southern Hemisphere 

 group and the Northern Hemisphere group. Both groups breed in trop- 

 ical coastal waters during the winters, then go to the Arctic or Antarctic 

 regionsfor summer feeding. The Fin, Sei, and Humpback whales migrate 

 seasonally in this fashion. 



Sperm whales appear in tropical waters the year round, seldom going 

 farther north than 40 degrees latitude. 



Most people do not realize that dolphins are small whales; dolphins 

 are also known as porpoises. 



Two species, the Amazon dolphin and the Ganges dolphin, actually 

 go into fresh waters of the Amazon and Ganges Rivers. 



The distribution and migration of whales is studied by means of com- 

 mercial catch records, tagging, and sightings. 



Some whale species are in danger of extinction because man has 

 overhunted. International agreements between whale hunting nations 

 attempt to limit the kill of certain species of whales. Through this in- 

 ternational effort, it is hoped that the whale stocks will be preserved for 

 future generations. 



Mackintosh, N. A. 



The Stocks of Whales, Fishing IMews Books Ltd., 1965. 



Slijper, E. J., W. L. Van Utrecht, and C. Naaktgeboren 



Remarks on the Distribution and Migration of Whales, Based on Ob- 

 servations from Netherlands Ships, Bijdragen Tot de Dierkunde, 1964. 



Norris, Kenneth S. 



Whales, Dolphins, and Porpoises, University of California Press, 

 Berkeley and Los Angeles, 1966. 



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