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proposed conservation regime. The lack of regulation 

 would be significant only in terms of the population of 

 that one species. Should numbers of southern blue whiting 

 decline, there would be at most a local impact on the rest 

 of the Antarctic ecosystem. It could be replaced by other 

 fish species in the diet of its predators. 



There is no present commercial interest in birds or 

 cephalopods in the Antarctic, although that cannot be ruled 

 out as future possibility. Hov/ever, no immediate direct 

 impacts on populations of birds and squid are expected. 



Harvesting of Antarctic seals under the Convention for 

 the Conservation of Antarctic Seals will only be regulated 

 south of 60°S latitude. Under the proposed conservation 

 regime, pelagic sealing could also be regulated between 

 60°S and the Convergence. Elephant and fur seals on islands 

 near the Convergence are not now harvested. 



3. Indirect Impacts on Dependent Species 



Concerns about the impacts of harvesting of one 

 species on others which are dependent on it are most per- 

 tinent to krill as the target species. Fish, squid, birds, 

 seals and whales depend on krill as a main food item, and 

 are in turn potential resources. 



Overexploitation of krill would be very dangerous to 

 the Antarctic ecosystem. Consider the history of whaling. 

 Most species of baleen whales have been reduced to roughly 

 a tenth of their populations of a century ago. This change 

 in whale numbers has caused some adjustments in other popu- 

 lations in the Antarctic ecosystem, but because whales are 

 the end of a food chain, the internal structure of the eco- 

 system has remained essentially unchanged. However, should 

 krill populations be reduced to a similar extent, enormous 

 reductions in populations of fish, squid, seals and also 

 whales would follow. Because of the crucial role of krill 

 in the Antarctic marine food web, overexploitation would 

 substantially alter the structure of the marine ecosystem 

 and substantially damage its health. 



Even without overexploitation, a large krill harvest 

 would affect populations of krill predators. Krill removed 

 by harvesting would come out of the total now consumed by 

 predators. With a decrease in available food, predator 

 populations in intensively harvested areas would drop. 



Fin, blue, hiompback and minke whales are presently 

 protected from harvest under the International Whaling 



