country" (Ford 1981). This is a policy that has been reiterated 

 many times, even when U.S. astronauts landed on the moon in 

 1969. Instead of claiming the moon for the United States alone, it 

 was claimed for all mankind. 



It was in this spirit that the United States persuaded Argentina, 

 Australia, Belgium, Chile, France, Japan, New Zealand, Norway, 

 South Africa, United Kingdom, and the U.S.S.R. to sign the An- 

 tarctic Treaty in 1959 which became effective in June 1961. Poland 

 later became signatory, thus becoming the 13th member. This 

 remarkable treaty reserved an entire continent for free and non- 

 political scientific investigation. 



Later, Brazil, Bulgaria, Czechoslovakia, Denmark, Federal 

 Republic of Germany, German Democratic Republic, 

 Netherlands, and Romania became signatories. It is highly unlikely 

 that the original land-claiming signatories of Antarctica at the time 

 of signing ever considered extending the Antarctic Treaty into the 

 contiguous seas. With the recent worldwide practice of extending 

 national jurisdiction seaward for 200 mi for fishery management 

 purposes, a point of disagreement might possibly intrude on an 

 otherwise amicable arrangement among the signatories. 



The area of greatest abundance of krill lies not far from areas 

 claimed by several nations. It is conceivable that after 1990 when 

 the present Antarctic Treaty expires claims may be made to extend 

 the jurisdiction of one or more nations seaward by 200 mi. Serious 

 discord and overlapping conflicting claims might well result not 

 only for the potential fisheries but also for unproved petroleum 

 reserves. The dispute between Argentina and Chile with respect to 

 the Beagle Channel claims of each nation might well be a precursor 

 of what may come. 



LOCATING AND HARVESTING KRILL 



The location (bringing a vessel to an area where there is a high 

 probability of catch) of krill by experienced fishermen is no more 

 difficult than it is for any other fishery (Eddie 1977). For the 

 relatively short summer period when climatic conditions favor a 

 krill fishery, usually dense swarms of krill are known to inhabit 

 certain areas more than others. Historically, the southern Atlantic, 

 more than the southern Pacific or the southern Indian Ocean, has 

 been the haunt of baleen whales. The chief areas of krill abun- 

 dance have been over the shelves and slopes and deeper water near 

 South Georgia, in the northern part of the Weddell Sea, in the 

 Scotia Sea north of the Orkney Islands, the South Sandwich 

 Islands, the South Shetland Islands, in the Bransfield Strait, and in 

 the Bellinghausen Sea (El Sayed and McWhinney 1979). Unpredic- 

 table occurrence of swarms is commonplace. In the 1979-80 season 

 the krill crop failed to materialize in the South Georgia area. Yet, 

 during 1980-81 First International Biomass Experiment (FIBEX) 

 observers detected a mass of krill estimated at 10 million t near the 

 South Shetland Islands. As Alverson (1979) stated "substantial 

 year-to-year variations in population sizes occur which are the 

 result of recruitment failure or changes in behavior or both." Sur- 

 face fishing strategy, in addition to visual location of swarms of 

 krill, also depends upon the presence of other natural indicator 

 predators such as birds, seals, and whales. 



The detection of deeper lying quantities of krill seems to be most 

 effective with the vertical echo sounder. The frequency of the 

 acoustic transmission used is between 100 and 200 kHz. For stocks 

 of krill not visible on or near the surface, fishing echo sounders can 

 be used to detect the fish which are feeding upon krill. Experienced 

 fishing skippers have, in some cases, been able to distinguish be- 

 tween desirable krill and unwanted salpas (Eddie 1977). As yet, it 



has not been possible to use echo sounders to distinguish between 

 krill of different sizes. The capability of acoustic devices to 

 discriminate between sizes of krill may depend on frequency, fre- 

 quency variation, beam width, and pulse length. It is generally 

 agreed by both scientists and experienced skippers that with the 

 present stocks of krill, location and detection, by and large, are not 

 much different from regular fishing operations (Eddie 1977). 



An unusual attempt at krill detection was reported to have been 

 developed by Japanese scientists of Tokyo University of Fisheries 

 for the 1978-79 exploration. A miniature model plane with a wing 

 span of about 2 m would be launched from the bow of the Univer- 

 sity research vessel Umitaka Maru. The model plane would have a 

 payload of 1 .5 kg and would carry two motor-driven cameras and 

 a transmitter capable of taking a total of 30 color and black-and- 

 white photographs. The plane would be able to ascend to about 

 1,200 m and reach a speed of about 83 km/h. Recovery of the 

 plane would be made with netting on the windward side of the 

 deck. The plane's engine revolutions, rudder, elevator, and two 

 cameras would be controlled from the deck of the ship by a hand- 

 held transmitter (Anonymous 1979). 



Several methods of capturing krill have been tried with varying 

 degrees of success. Efforts have been made to use single-boat and 

 two-boat purse seines, but efforts to use any kind of purse seines 

 have been given up because 1) it is expensive and very difficult to 

 repair seines, and 2) purse seining is primarily a good weather 

 operation. The summer weather in the Antarctic is usually foul and 

 very often dangerously windy for this method of capture. The 

 most effective methods appear to be variations in surface- 

 midwater trawls. 



Early attempts at harvesting krill were based on the assumption 

 that patches of krill were to be found chiefly at or near the surface 

 of the ocean. It was also assumed that krill could take evasive ac- 

 tion to avoid an approaching net or ship. (The 1981 FIBEX cruise 

 confirmed that krill can avoid the nets.) It was considered that a 

 ship plowing through a swarm would scatter the krill and that the 

 best way to catch them would be to tow a surface trawl with a 

 mouth opening wider than the trawler. Another method was to use 

 an outrigger on each side of the trawler each one of which towed a 

 surface trawl. An additional method was to tow a trawl on the sur- 

 face and have the ship move in a curved path so that the trawl 

 would not follow in the wake of the trawler. Another method was 

 to affix a net to a metal frame that would form an inflexible mouth 

 opening of the net. The whole arrangement was suspended from 

 the side of the ship and some attempts even included the principle 

 of continuous discharge by pump and flexible hose to a screen on 

 the trawler deck. The screen retained the krill and the seawater 

 escaped via the scuppers. Again, this type of catching-unloading is 

 good only for surface krill, and it operates reasonably well only in 

 calm weather which is a scarce commodity in the Antarctic (Eddie 

 1977). 



Only recently (1970's) was it appreciated that patches of krill 

 could be located well below the ocean surface in large quantities. 

 By means of echo sounders and well designed krill trawls in the 

 hands of skilled fishing captains, it has been established that aimed 

 midwater trawls shot by single trawlers are the most efficient krill 

 catchers (except whales). 



Practical catching rates can be achieved by using much smaller 

 trawls than are used in conventional fisheries. The increased drag 

 caused by the use of small mesh in order to contain the krill 

 without escapement, necessitates the use of smaller trawl nets. An 

 alternative is to use a relatively large mesh trawl with a fine mesh 

 liner. Mesh sizes for krill have ranged from as little as 8 mm (stret- 

 ched) to as great as 12 to 24 mm. 



