Chapter IV — International 



tion on the nature of the proposed fishery and baseline 

 information on such things as the discreteness, distri- 

 bution, abundance, and productivity of the stock or 

 stocks that would be affected by the fishery. 



Assessment and Avoidance of Incidental Mortali- 

 ty — In recent years, there have been reports of 

 significant seabird mortality associated with the 

 longline fishery for Dissostichus eleginoides. Data 

 provided for consideration during the 1991 meetings 

 of the Living Resources Commission and Scientific 

 Committee suggest that 1,700 birds, including 580 

 albatrosses, may have been caught and killed inciden- 

 tal to longline fishing in Sub-area 48.3 during the 

 1990-91 season. There also is evidence that substan- 

 tial numbers of seabirds may collide with and become 

 entangled in cables used to monitor trawl nets. To 

 minimize such incidental mortality, the Commission, 

 acting on the advice of the Scientific Committee, 

 adopted conservation measures: (1) prohibiting the 

 use of net monitor cables on fishing vessels in the 

 Convention Area after the 1993/94 fishing season; and 

 (2) requiring that longline fishing operations be con- 

 ducted using a streamer line to discourage birds from 

 settling on baits during deployment of longlines and 

 that operations be conducted in such a way that the 

 baited hooks sink as soon as possible after they are 

 put into the water. 



On a more positive note, information presented 

 during the 1991 meeting of the Scientific Committee 

 indicated that the number of fur seals found entangled 

 in net debris at Bird Island, South Georgia, had 

 declined by approximately 80 percent over the past 

 two years, possibly reflecting positive results in 

 efforts to stop dumping debris at sea. 



Ecosystem Monitoring — The Convention for the 

 Conservation of Antarctic Marine Living Resources 

 requires that fishing and related activities in the 

 Convention Area be managed to prevent irreversible 

 changes in the structure and dynamics of the Antarctic 

 marine ecosystem, as well as to prevent overfishing 

 and depletion of harvested populations. In 1984, the 

 Scienfific Committee for the Conservation of Antarctic 

 Marine Living Resources established a working group 

 to formulate and coordinate implementation of a 

 multi-national research program to assess and monitor 

 the status of key components of the Antarctic marine 



ecosystem. Since then, the working group has devel- 

 oped and members have begun implementing a long- 

 range program plan, with three major components: 



(1) monitoring of representative, land-breeding krill 

 predators (e.g., Antarctic fur seals and Adelie pen- 

 guins) at a network of sites throughout the Antarctic; 



(2) comprehensive studies of krill, krill predators, and 

 related environmental variables in three integrated 

 study areas (Prydz Bay, the Bransfield Strait, and the 

 area around South Georgia Island); and (3) directed 

 studies of the demography and dynamics of crabeater 

 seals in one or more pack ice areas. The working 

 group also has initiated development of standard 

 methods and formats for collecting and reporting 

 various types of predator, prey, and environmental 

 data. In addition, it has recommended that provision 

 be made to afford special protection to sites where 

 monitoring programs are being conducted. 



The working group met at Santa Cruz de Tenerife, 

 Spain, from 5-13 August 1991. The working group 

 report, considered during the Scientific Committee's 

 meeting, proposed that a workshop be held to review 

 available information and identify the most appropri- 

 ate procedures and technology for obtaining informa- 

 tion on the at-sea behavior of penguins and pinnipeds. 

 The group recommended that a pilot study be conduct- 

 ed, at two of the existing monitoring sites, to deter- 

 mine how satellite imagery might be used to obtain an 

 index of sea ice information within the general forag- 

 ing range of the krill predators being monitored at the 

 site. To allow formulation of management advice 

 based on comparative evaluation of predator, prey and 

 environmental data, the working group requested that 

 members annually make available data on the fine- 

 scale distribution of krill catches, estimates of krill 

 biomass and movements, and relevant environmental 

 data from areas within the foraging range of krill 

 predators at the sites being monitored. The working 

 group noted that myctophids, particularly Electrona 

 carlsbergi and E. antarctica, are important prey for a 

 wide range of vertebrate predators and that there 

 consequently is a significant likelihood of the rapidly 

 expanding myctophid fishery adversely affecting 

 vertebrate species dependent upon myctophids. 



The Scientific Committee and Commission en- 

 dorsed the working group's proposals. In addition, 

 the Commission provisionally endorsed a management 



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