FISHERY BULLETIN: VOL. 80, NO. 3 



from this region prevents its analysis; the results 

 presented here pertain only to the eight main 

 islands of the archipelago (Hawaii, Maui, 

 Kahoolawe, Lanai, Molokai, Oahu, Kauai, and 

 Niihau, including Kaula Rock). Within this 

 region fishing is conducted on offshore banks 

 and pinnacles, primarily in the vicinity of the 

 100-fathom isobath. In the Hawaiian Islands the 

 sea bottom typically extends away from shore at 

 a depth of 30 fathoms for some distance and then 

 falls abruptly to very great depths over a 

 relatively short horizontal span (Brock and 

 Chamberlain 1968). Most fishing occurs in this 

 steep dropoff zone. Hence it is possible to crudely 

 estimate the relative amount of total bottom fish 

 habitat around a fishing bank by determining 

 the length of the 100-fathom isobath surround- 

 ing it (Table 2). The maximum depth between 

 the islands of Maui, Lanai, Kahoolawe, and 

 Molokai (MLKM) is <100 fathoms; therefore, 

 they were pooled and treated as a single bank 

 (Fig. 2). All bottom fish taken from a bank were 

 considered one stock because movements of 

 juveniles and adults across deep water from one 

 bank to the next are highly improbable whereas 

 lateral movements around the perimeter of the 

 100-fathom isobath of a bank cannot be dis- 

 counted. The Islands of Oahu and Hawaii are 

 separated by deep water from all other islands 

 and banks, hence, by definition, they harbor 

 distinct stocks. Kauai, Niihau, and Kaula Rock 



Table 2.— A list of the four banks which harbor separately 

 defined stocks. The length of the 100-fathom isobath around a 

 bank roughly measures the extent of its bottom fish habitat. 



'Maui-Lanai-Kahoolawe-Molokai. 

 2 Kauai, Niihau. and Kaula Rock 



(KNK), although separated across short dis- 

 tances by deep water, were analyzed together 

 because they present a similar fishing profile 

 and they are closely situated to one another. 

 Thus, based on this classification four distinct 

 stocks were analyzed independently. The extent 

 of larval dispersal between these stocks is 

 unknown at present but is currently under study 

 (Shaklee 6 ). A more detailed description of this 

 fishery may be found in Ralston (footnote 4) or in 

 Hawaii Department of Land and Natural Re- 

 sources (1979). 



FISHING EFFORT 



The ultimate goal of any stock-production 

 analysis is to relate the impact of variable fishing 

 pressure on stock abundance. Fishing pressure 



6 J. G. Shaklee, Hawaii Institute of Marine Biology, Uni- 

 versity of Hawaii, Kaneohe, HI 96744, pers. commun. 1979. 



*£i^> 



{</■ Miihau 

 'Kaula 



)Kauai 



W 



Molokai 



,.,oo-' 



Lanai 

 Kahoolawe:^ 



N 

 -22° 



160° W 159° 



l I 



158° 



i 



157° 



FIGURE 2.— Map of the eight main Hawaiian Islands and Kaula Rock with the 100-fathom 



isobath included. 



438 



