contained numerous crabs and seemed to be in good 

 working order. 



Interviews with fishermen revealed common causes of 

 pot loss including: 1) buoyline breakage from chafing or 

 entanglement in vessel propellers; 2) buoy puncture by 

 sea lions; 3) pots carried into deeper water when tangled 

 in gear such as trawls, longline, or other pots; and 4) 

 buoyline entanglement during set, so line is too short and 

 buoys are carried under the surface. 



MAGNITUDE OF POT LOSS 



The year 1960 was the beginning of rapid growth in 

 U.S. king crab fishing. By 1964, about 270 vessels par- 

 ticipated in the fishery. The number of pots fished varied 

 greatly among vessels because of variations in vessel size 

 and changing Alaska regulatory limits for pots fished per 

 vessel. In the 1969-70 season, 354 vessels fished an aver- 

 age of 70 [jots each (Rod Kaiser, see footnote 3). Fisher- 

 men generally agree that about 10% of their pots are lost 

 each season. Some vessels reported pot losses of up to 

 50%, but such losses were uncommon. 



To develop an estimated number of lost pots, we as- 

 sume that 300 vessels fished an average of 60 pots each 

 per year from 1960 to 1975. About 10%, or 27,000, of the 

 270,000 pots fished during the 15 yr may have been lost. 

 Based upon the engineering longevity estimate of 15 yr 

 for pots (Richard McNeely*), we can assume that many 

 lost pots may still be fishing. The others would no longer 

 catch crabs because of damage by fishing gear — such as 

 trawl, longline, and other pots — or because of environ- 

 mental conditions — such as pots settling into sand at 

 shallow depths (Rearden 1976). Sea lions could also have 

 damaged the pots. 



In view of those estimates, and from interviews with 

 fishermen, we conclude that there are thousands of pots 

 in fishing condition lying on commercial crab grounds. 

 Occasional derelict pot recoveries confirm that crabs 

 continue to enter them (Fig. 1). The problem of derelict 

 pots, then, lies with the number of fishable pots and the 

 mortality of crabs entering them. 



■•Richard McNeely, Northwest and Alaska Fisheries Center, National 

 Marine Fisheries Service, NOAA, Seattle. WA 98112, pers. commun., 

 December 1976. 



i 



Figure 1. — This abandoned Japanese-type snow crab pot. recovered 3 mo after close of the 

 commercial fishing season, contained 12 king crab and 14 snow crab. One of each species 

 was dead. 



