!ase of the Missing Lobsters 



What does a low-pressure system over the North Pacific have to do 

 with the complaints of disgruntled lohstermen? 



' ' %* 



by Jeffrey Polovina 



From the main islands of Hawaii, 

 countless small islands, atolls, and sub- 

 merged banks stretch northwestward a 

 thousand miles to Midway Island. The is- 

 lands are part of a wildlife refuge, and ex- 

 cept for a few biologists camped out at re- 

 search stations, they are uninhabited. The 

 archipelago supports a wealth of marine 

 life, including a large population of 

 seabirds and a small population (1,600) of 

 Hawaiian monk seals, an endangered spe- 

 cies. This is where, in recent years, loh- 

 stermen have begun to harvest Pacific 

 spiny lobsters. 



As a marine biologist with the National 

 Marine Fisheries Service in Honolulu 

 since 1979, my job has been to provide 

 lobstermen and managers of the fisheries 

 in the northwestern Hawaiian Islands with 

 biological advice. Thus, I am no stranger 

 to phone calls from unhappy or even irate 

 lobstermen. I still remember a call I re- 

 ceived in September 1989. The caller was 

 not angry despite his recent return from a 

 sixty-day fishing trip that had yielded a 

 very poor lobster catch. He was puzzled, 

 however, because on a trip to the same 

 areas a few months before, the catch had 

 been excellent. I told him the reason for 

 the drop was obvious; he had fished out all 

 the lobsters! He was not amused. So I sug- 

 gested that the low catch was just a tempo- 

 rary aberration. I reminded him that in 

 1987, colder water seemed to have re- 

 stricted spiny lobsters' movements, mak- 

 ing them harder to trap, and that by 1988, 

 more favorable conditions — and good 

 catches — had returned. I even went as far 

 as telling him that he should look forward 

 to a good year in 1990. 



That was a mistake. By the summer of 

 1990, lobster catches had not improved, 

 and my advice was proving to be an em- 

 barrassment. With fishermen grumbling 

 and managers becoming nervous, I was 

 under pressure to find the real reason for 

 the persistent decline in lobsters. 



Although my first reaction had been to 

 blame the lobster decline on the usual sus- 

 pect, overfishing, I had a number of rea- 

 sons to doubt that this was the cause. First, 

 the proportion of the lobster population 



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