A Social and Economic Characterization of the U.S. Gulf of Mexico Recreational Shark Fishery

A mail survey of tournament shark anglers and party boat shark anglers was completed to examine their fishing activity, attitudes, trip expenditures, and consumer surplus. A sample of 700 shark anglers was selected from tournaments in the Gulf of Mexico during 1990, and a sample of party boat shark anglers was drawn from Port Aransas, Tex., party boat anglers during the summer of 1991. A response rate of 58% (excluding nondeliverables) was obtained from tournament anglers. The sample of party boat shark anglers was too small to provide useful results. Tournament shark anglers reported fishing an average of 58 days per year and targeted sharks and other large marine species. Tournaments occupy a small portion of their fishing effort. If this group of anglers were not able to fish for sharks, one-third indicated no other species would be an acceptable substitute, while others were willing to substitute other large marine species. Shark trip expenditures averaged $197 per trip with a consumer surplus of $111 per trip. Based on MRFSS estimates of the number of shark fishing trips, we estimate a total of $43,355,000 was spent by shark anglers in the Gulf of Mexico with a consumer surplus of $23,865,000 for a total gross value of the shark fishery of $66,220,000. MRFSS estimates of the number of sharks landed indicate an equivalent use value of $183 per shark.

Biology and Management of Deepwater Snappers of the Hawaiian Archipelago

Commercial and recreational deepwater (100-400 m) bottom-fishing in Hawaii targets a multispecies group of lutjanid snappers. Relatively little is known about the life history of these species. Research in Hawaii and elsewhere in the tropical Pacific suggests that most of the species are slow growing, long lived, and have a relatively high age at sexual maturity. Stock assessment is difficult because of the multispecies nature of the fishery. However, recent analysis of commercial fishery data indicates that some of the species may currently be overexploited. Research is underway to determine the efficacy of management measures such as minimum-size limit changes or seasonal and spatial fishery closures to maintain optimal spawning biomass.

Population Biology and Life History of the North American Menhadens, Brevoortia spp.

Four recognized species of menhaden, Brevoortia spp., occur in North American marine waters: Atlantic menhaden, B. tyrannus; Gulf menhaden, B. patronus; yellowfin menhaden. B. smithi; and finescale menhaden, B. gunteri. Three of the menhaden species are known to form two hybrid types. Members of the genus range from coastal waters of Veracruz, Mex., to Nova Scotia, Can. Atlantic and Gulf menhaden are extremely abundant within their respective ranges and support extensive purse-seine reduction (to fish meal and oil) fisheries. All menhaden species are estuarine dependent through late larval and juvenile stages. Depending on species and location within the range, spawning may occur within bays and sounds to a substantial distance offshore. Menhaden are considered to be filter-feeding, planktivorous omnivores as juveniles and adults. Menhaden eggs, immature developmental stages, and adults are potential prey for a large and diverse number of predators. North American menhadens, including two hybrids, are hosts for the parasitic isopod, Olencira praegustator, and the parasitic copepod, Lemaeenicus radiatus. Although the data are quite variable, a dome-shaped Ricker function is frequently used to describe the spawner-recruitment relationship for Atlantic and Gulf menhaden. Each of these species is treated as a single stock with respect to exploitation by the purse-seine reduction fishery. Estimates of instantaneous natural (other) mortality rates are O.45 for Atlantic menhaden and 1.1 for Gulf menhaden.

Acid waters in North West England. The effect of liming agricultural land

This is the Acid waters in North West England: The effect of liming agricultural land on the chemistry and biology of the River Esk, North West England report produced by National Rivers Authority in 1992. This report focuses on the study of Acid Waters in the North West Region of England, UK, which began in 1982 and sampling was completed in October 1990. This work was initiated because of the observation of the simultaneous mortality of adult and juvenile salmon and sea-trout in both the River Esk and adjacent River Duddon in June 1980. Investigations at that time indicated that an "acid episode" was the most likely cause of this mortality. A land use study indicated that a reduction in agricultural liming may have been a major factor in the development of acid episodes and consequent fish kills in the River Esk and River Duddon. However there was no evidence that the mortalities of salmonids in the early 1980's were due to a reduction in agricultural liming. They were due to some other phenomenon such as a period of intense acid deposition.