Toxicidade aguda sobre Daphnia similis decorrente de contamina����o aqu��tica recente e antiga por gasolina, etanol e suas misturas: simula����es em escala de bancada.

A contamina����o de ambientes aqu��ticos decorrente de acidentes com gasolina, ��lcool combust��vel e misturas bin��rias representa um risco crescente, tendo em vista as proje����es do setor para os pr��ximos 50 anos. O objetivo do presente estudo foi avaliar a toxicidade aguda da Gasolina C, Gasolina P e ��lcool combust��vel isoladamente e em misturas bin��rias, assim como de suas respectivas Fra����es Sol��veis em ��gua (FSA) e Fra����es Dispersas em ��gua (FDA) sobre Daphnia similis. O estudo ainda incluiu a avalia����o da toxicidade aguda remanescente na matriz ��gua de uma contamina����o antiga (intemperismo) com a Gasolina C. Paralelamente, foram conduzidos ensaios de toxicidade aguda com amostras ambientais (��gua subterr��nea, superficial e elutriato a partir de sedimentos) de uma ��rea alagada com hist��rico de contamina����o antiga. O cultivo e os ensaios com D. similis foram de acordo com a NBR 12.713 (2009). Tanto a gasolina C quanto a P foram extremamente t��xicas para os organismos, apresentando valores m��dios de CE50% em 48 h de 0,00113% e 0,058% respectivamente. As diferen��as entre os resultados obtidos com a Gasolina C e aqueles obtidos com suas fra����es FSA e FDA foram significativas (p < 0,05), sendo que n��o houve diferen��a significativa entre a toxicidade aguda da FSA e da FDA (p < 0,05). Os resultados obtidos com os ensaios com Gasolina P e FDA n��o apresentaram diferen��as significativas entre si (p < 0,05), mas, foram significativamente diferentes daqueles obtidos com FSA (p < 0,05). Os resultados dos ensaios de toxicidade aguda com misturas bin��rias sugeriram efeito menos que aditivo (antagonismo). Os resultados da simula����o de uma contamina����o antiga demonstraram redu����o acentuada da toxicidade para D. similis ao longo de apenas 28 dias. Entretanto, com rela����o aos ensaios com as amostras ambientais da ��rea com hist��rico de contamina����o, apesar da aus��ncia ou baixa toxicidade nas amostras de ��gua superficial (sugerindo intemperismo), toxicidade alta foi observada em amostras de ��gua subterr��nea e no elutriato de sedimentos, sugerindo condi����es de adsor����o aos sedimentos com alto teor de argila e/ou aprisionamento dos compostos em zona saturada.

The Oyster Industry of Eastern Mexico

Mexico has an oyster industry of substantial size, ranking about sixth in the world. In 1993, among the top ten oyster producers, Korea, Japan, the United States, China, and France ranked ahead of Mexico, while the Philippines, Australia, Canada, and New Zealand trailed it (Fig. 1). On its east coast, the species landed is the eastern oyster, Crassostrea virginica, while on its west coast C. corteziensis, C. iridescens, and the Pacific oyster, C. gigas, are landed. During the last 10-15 years, annual production often was at least 50,000 t of shelled oysters, or nearly 1.5 million bushels (Anonymous, 1995), with the great preponderance (90%) coming from a series of lagoons connecting with the Gulf of Mexico along the east coast (Fig. 2) and the remainder produced on the west coast.

The U.S. Gulf of Mexico Party Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

In addition to providing an overview of the party boat fishery in the U.S. Gulf of Mexico, a management-oriented methodology is presented that can be used elsewhere to assess regulatory impacts. Party boat operators were interviewed to determine species targeted, percent time committed to targeting each species, and opinions on current catch restrictions. Over two-thirds of the fieet was located on the west coast of Florida. Overall, most boats targeted <5 species. Four species accounted for 90 percent of the estimated effort by party boats in the U.S. Gulf of Mexico: Snapper; Lutjanus sp.; grouper, Epinephelus sp. and Mycteroperca sp.; amberjack, Seriola dumerili; and king mackerel, Scomberomorus cavalla. Party boat effort in Texas was devoted primarily to snapper, whereas in Florida most effort was devoted to snapper and grouper collectively. Party boat operators were diverse in their opinions of management regulations in force when interviewed. Results revealed why major opposition would he expected from Texas party boat operators for red snapper bag limits and other restrictions proposed by the Gulf of Mexico Fishery Management Council.

The U.S. Gulf of Mexico Charter Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

The charter boat industry in U. S. Gulf of Mexico provides access to offshore fishing opportunities for about 570,000 passengers per year on 971 boats. A 25% random sample of charter boat operators was interviewed during 1987-88 to determine species targeted, percent time committed to targeting each species, and reactions to existing catch restrictions. Three-fourths of the charter boat fleet was in Florida, 13% in Texas, 5% in Louisiana, 4% in Alabama, and 2% in Mississippi. Responses were diverse regarding species focus within the region. Species of dominant importance included groupers, Epinephelus sp. and Mycteroperca sp. (Fla.); snapper, Lutjanus campechanus (Ala., Fla., Miss., and La.); king mackerel, Scomberomorus cavalla (Miss., Tex., Ala. and Fla.); spotted seatrout, Cynoscion nebulosus (Tex. and La.); and red drum, Sciaenops ocellatus (Tex. and La). Catch restrictions were generally supported with higher levels of opposition to restricted high effort fish and/or one fish or closed fishery limits.

Menhaden: The Resource, The Industry, and a Management History

PREFACE: Four species of menhaden, Brevoortia spp., are found along the Atlantic and Gulf of Mexico coasts of the United States. The Atlantic menhaden, B. tyrannus, is found from Nova Scotia, Can., to West Palm Beach, Fla.; the yellowfin menhaden, B. smithi, is found from Cape Lookout, N. C., to the Mississippi River Delta, La.;the Gulf menhaden, B. patronus, is found from Cape Sable, Fla., to Veracruz, Mex.; and the finescale menhaden, B. gunteri, is found from the Mississippi River Delta, La., to Campeche, Mex. Menhaden are euryhaline species that inhabit coastal and inland tidal waters. Spawning occurs principally at sea (in northern areas some spawning occurs in bays and sounds). Eggs hatch at sea and the larvae are moved to estuaries by ocean currents where they metamorphose and develop as juveniles.

Competing for the Recreational Dollar: An Analysis of the California Commercial Passenger-Carrying Fishing Vessel Industry

California has a large and diverse marine recreational fishery. Anglers on commercial passenger-carrying fishing vessels (CPFV's) harvest a substantial proportion of California's marine recreational fisheries landings, accounting for about 40 percent and 16 percent of the total 1986 marine recreational catch in southern and northern California, respectively (NMFS, 1987). In 1986, 459,369 CPFV anglers landed some 2,835,021 fish in southern California, while 200,925 CPFV anglers landed 1,240, 100 fish in central and northern California.