Recreational Landings Research Articles

Total mercury levels in tunas from offshore waters of the Florida Atlantic coast

Yellowfin tuna (Thunnus albacares), blackfin tuna (T. atlanticus), and little tunny (Euthynnus alletteratus), support significant recreational and commercial fisheries in Florida and throughout their respective ranges. Greater than 2.7 million pounds of these three tuna species were landed in Florida during 2002 (National Marine Fisheries Service, Fisheries Statistics and Economic Division, personal communication). The majority of recreational landings of blackfin tuna and little tunny in the southeastern United States are typically from Florida waters (National Marine Fisheries Service, Fisheries Statistics and Economic Division, personal communication). Although mercury and other contaminants in tunas and other pelagic species are of widespread interest and concern, data regarding mercury levels in tunas from the southeastern United States are very limited. Due to the current lack of information, increased monitoring of mercury in these species has been recommended by both state and federal fishery agencies. Fish-consumption advisories issued by the Florida Department of Health (DOH) for mercury in fish from Florida waters currently include blackfin tuna and little tunny (DOH, 2003). This advisory urges limited consumption of blackfin tuna from waters off the central Atlantic coast of Florida and limited consumption of little tunny from all Florida coastal waters (DOH, 2003). The objectives of this study were to analyze and interpret the total mercury content in dorsal muscle tissue of yellowfin tuna, blackfin tuna, and little tunny collected from coastal and offshore waters Florida’s Atlantic coast from 1999 to 2002. This study will also provide critical data to public health agencies within the State of Florida and elsewhere in the region to assess potential public health issues related to mercury concentrations in tunas from Florida and adjacent states in the southeastern United States.

Dolphinfish fisheries in the Caribbean region

Dolphinfish are targeted throughout the Western Central Atlantic region by recreational fishers, small-scale artisanal fishers, and small longliners. They are also taken as by-catch on large-scale commercial longlines. Catches are highly seasonal and exhibit considerable interannual variability. According to the landing statistics provided by countries to FAO, dolphinfish ranked seventh overall in reported average annual landings of large pelagic fishes in the Western Central Atlantic from 1989 to 1993. Yellowfin tuna, Spanish mackerel, skipjack tuna, king mackerel, swordfish and Atlantic bonito ranked ahead of dolphinfish. There is a trend of increasing total annual landings from about 1,700 mt in 1970-74 to about 2,800 mt in 1989-1993. Landings are reported to FAO by only eight countries, whereas dolphinfish are known to be caught in most of the region´s 34 countries. By-catch on longlines and recreational landings are also largely unreported. Therefore, it is likely that the reported landings are a substantial underestimate. The relative importance of dolphinfish to pelagic fisheries varies from one part of the region to another. In the Lesser Antilles it is the most important large pelagic fish in terms of amounts landed. The absence of a large-scale commercial fishery targeting dolphinfish appears to have resulted in a lack of recognition of its contribution, particularly in developing countries of the region. Consequently, its biology and assessment have been neglected in relation to the attention given to other large pelagic fishes, mainly tunas and tuna-like fishes which have been the focus of ICCAT assessment activities.

Characterization of the dolphinfish (Coryphaenidae) fishery of the United States western north Atlantic Ocean

Fishery dependent data from various commercial and recreational sampling programs form the basis for characterizing the fishery for dolphinfish (Coryphaenus hippurus) in the waters of the Gulf of Mexico and off the southeastern U.S. coast. Three states in the region have implemented size and bag limits for dolphinfishes, but there are no federal regulations in place at this time. Commercial landings were relatively small in comparison to recreational landings from 1984 through 1996. In 1995 however, commercial landings in the Atlantic Ocean of the southeastern U.S. were almost twice the weight of the previous years. The average weight per fish was calculated for each water body and fishing sector and there appear to have been significant increases in the average weight of fish landed both in the commercial and recreational sectors in the Atlantic and the Gulf of Mexico. Catch per unit of effort is measured as numbers of fish caught per angler per hour in the recreational fishery and has been variable since the early 1980s. In light of increasing landings and average weights of fish landed since the 1980s, the sustainability of this fishery must be fully evaluated.

Trends in the Commercial and Recreational Shark Fisheries in Florida, 1980–1992, with Implications for Management

Florida commercial shark landings rose from 287,531 lb in 1980 to 7.3 million pounds in 1990, an increase of more than 2,400%. Two reasons for this increase in landings were the growing public acceptance of shark meat as a seafood product and the subsequent increase in prices in the Asian market for shark fins. Landings then declined in 1991 and 1992. Commercial and recreational landings data and responses to mail surveys have supplied important information regarding Florida's shark fisheries. The sandbar shark Carcharhinus plumbeus and the blacktip shark C. limbatus accounted for 84% of the sharks landed in the commercial fishery in 1989. Commercially fished sharks are captured primarily by longline gear. After 1986, sharks were targeted much more frequently in the commercial fishery. Although catch per unit of effort steadily increased, landings and effort decreased during the 2 years before the implementation of regulations. Fewer sharks were landed in the recreational fisheries than in the commercial fisheries after 1986. Recreational landings declined considerably from 1990 to 1992, and the species of sharks landed differed from those landed in the commercial fishery. During the 1930s and 1940s, sharks were easily overexploited, so the recreational and commercial fisheries' ability to sustain elevated harvest levels is currently very much in question. Shark life history data explains this potential vulnerability to overfishing. Resource managers have used detailed fishery data and life history information to develop regulations that will help reduce the overexploitation of shark species in waters adjacent to Florida.

Status and Trends of White Abalone at the California Channel Islands

Abstract The white abalone Haliotis sorenseni occupied rocky reefs in high densities around the California Channel Islands at depths of 26–65 m in the early 1970s. By 1981, white abalone densities had declined two orders of magnitude, and the species had virtually disappeared by the early 1990s. From April 1992 through December 1993, we searched 30,600 m2 of suitable habitat at 15 locations known previously to support the white abalone. We found three live individuals (mean density, 0.0002/m2; SE, 0.0005). All three were near the maximum size common for the white abalone. At average densities, an equivalent search in the 1970s would have revealed 6,120–30,600 adults. Fishery landings reflected this population collapse. Annual commercial landings averaged 41 metric tons in 1971–1976, peaked abruptly at 65 tons in 1972, then plummeted to 0.140 ton in 1981; landings averaged only 0.153 ton from 1991 through 1994. Recreational landings, never numerous, virtually ceased after 1983. During the 1992–1993 survey,...

An examination of sexual dimorphism in Atlantic and Pacific blue marlin using body weight, sagittae weight, and age estimates

Length, weight and otoliths of Atlantic and Pacific blue marlin ( n = 436) were sampled between 1979 and 1983 in the Atlantic and Pacific Oceans from recreational landings. Otolith weight was highly variable within size classes, but the range of otolith weights was the same for males and females from both oceans. Although age estimates for Atlantic and Pacific blue marlin were not validated, males and females were estimated to be equally long-lived, reaching estimated ages of >20 yr, yet females achieve much larger somatic sizes than males. Length was not useful in predicting estimated age. The sex-related size differences in Atlantic and Pacific blue marlin can be attributed to differential growth between sexes. Although males can grow to a maximum size of ∼ 160 kg and females grow to at least 540 kg, longevity was similar for both sexes. The sex-related size differences in blue marlin are related to differential growth between sexes and are not due to differential mortality. Otolith weight was linearly related to estimated age and r 2 ranged from 0.70 to 0.91 for Atlantic and Pacific blue marlin. This relationship demonstrates potential for estimating the age structure of the landings, if validation of the aging method can be achieved.