On the Management of Blue Marlin and White Marlin in the Atlantic: Implications for Foreign Longlining and Domestic Sportsfishing

Tundi M. Agardy, University of Rhode Island


The twentieth century has witnessed the exponential growth of world-wide populations, and with it the over-exploitation of previously abundant resources. The limits inherent in terrestrial food production have necessitated increased utilization of world marine resources. Improved technology has enabled fishing fleets to harvest with a level of efficiency that in many cases has endangered the existence of commercial fishstocks. In the northwestern Atlantic, the price of ever-increasing harvesting has been the near decimation of several species. Haddock, herring and bluefin tuna are only a few stocks which have suffered from over-fishing. Blue marlin and white marlin are two species which have similarly been exploited with greater and greater frequency, but for very different reasons. Being large, predatory fish that are often found in association with yellowfin and other tunas, marlin are susceptible to being caught as by-catch in fisheries primarily directed at tuna. That the incidental by-catch of non-tuna species on longline is in high proportion to total catch is not news, but that this incidental catch might seriously affect fishstocks is only now becoming apparent. In fact, until L. J. Hoey presented his dissertation on the composition of longline by-catch, virtually nothing was known about how longlining activities in the north Atlantic might be affecting the ecology of the region.