Size-composition of Annual Landings in the White Shrimp, Litopenaeus setiferus, Fishery of the Northern Gulf of Mexico, 1960–2006: Its Trend and Relationships with Other Fishery-dependent Variable

The potential for growth overfishing in the white shrimp, Litopenaeus setiferus, fishery of the northern Gulf of Mexico appears to have been of limited concern to Federal or state shrimp management entities, following the cataclysmic drop in white shrimp abundance in the 1940’s. As expected from surplus production theory, a decrease in size of shrimp in the annual landings accompanies increasing fishing effort, and can eventually reduce the value of the landings. Growth overfishing can exacerbate such decline in value of the annual landings. We characterize trends in size-composition of annual landings and other annual fishery-dependent variables in this fishery to determine relationships between selected pairs of these variables and to determine whether growth overfishing occurred during 1960–2006. Signs of growth overfishing were equivocal. For example, as nominal fishing effort increased, the initially upward, decelerating trend in annual yield approached a local maximum in the 1980’s. However, an accelerating upward trend in yield followed as effort continued to increase. Yield then reached its highest point in the time series in 2006, as nominal fishing effort declined due to exogenous factors outside the control of shrimp fishery managers. The quadratic relationship between annual yield and nominal fishing effort exhibited a local maximum of 5.24(107) pounds (≈ MSY) at a nominal fishing effort level of 1.38(105) days fished. However, annual yield showed a continuous increase with decrease in size of shrimp in the landings. Annual inflation-adjusted ex-vessel value of the landings peaked in 1989, preceded by a peak in annual inflation-adjusted ex-vessel value per pound (i.e. price) in 1983. Changes in size composition of shrimp landings and their economic effects should be included among guidelines for future management of this white shrimp

Yellowfin Sole, Pleuronectes asper, of the Eastern Bering Sea: Biological Characteristics, History of Exploitation, and Management

Yellowfin sole, Pleuronectes asper, is the second most abundant flatfish in the North Pacific Ocean and is most highly concentrated in the eastern Bering Sea. It has been a target species in the eastern Bering Sea since the mid-1950's, initially by foreign distant-water fisheries but more recently by U.S. fisheries. Annual commercial catches since 1959 have ranged from 42,000 to 554,000 metric tons (t). Yellowfin sole is a relatively small flatfish averaging about 26 cm in length and 200 g in weight in commercial catches. It is distributed from nearshore waters to depths of about 100 m in the eastern Bering Sea in summer, but moves to deeper water in winter to escape sea ice. Yellowfin sole is a benthopelagic feeder. It is a longlived species (>20 years) with a correspondingly low natural mortality rate estimated at 0.12. After being overexploited during the early years of the fishery and suffering a substantial decline in stock abundance, the resource has recovered and is currently in excellent condition. The biomass during the 1980's may have been as high as, if not higher than, that at the beginning of the fishery. Based on results of demersal trawl surveys and two age structured models, the current exploitable biomass has been estimated to range between 1.9 and 2.6 million t. Appropriate harvest strategies were investigated under a range of possible recruitment levels. The recommended harvest level was calculated by multiplying the yield derived from the FOI harvest level (161 g at F = 0.14) hy an average recruitment value resulting in a commercial harvest of 276,900 t, or about 14% of the estimated exploitable biomass.

Otimização da co-pirólise de gasóleo pesado com embalagens de PEAD pós-uso utilizando planejamento fatorial

A co-pirólise é uma rota promissora, uma vez que minimiza o impacto ambiental causado pela disposição do plástico de maneira inadequada, evita seu acúmulo em lixões e permite um melhor aproveitamento de um recurso natural não-renovável, o petróleo, matéria prima importante para a geração de energia e obtenção de produtos químicos. O presente trabalho teve como objetivo a definição das condições experimentais mais propícias à obtenção de líquidos pirolíticos com alta fração de óleo diesel, resultantes da co-pirólise de polietileno de alta densidade (PEAD) pós-consumo com gasóleo pesado tilizando-se catalisador de FCC (Fluid Catalytic Cracking). Como instrumento de otimização das condições experimentais, optou-se pela Metodologia Planejamento Fatorial. Foi também estudado o efeito das condições experimentais, como: a temperatura de reação, a relação gasóleo/polietileno e a quantidade de catalisador no meio reacional. As amostras de polietileno, gasóleo e catalisador foram submetidas à co-pirólise em sistema de leito fixo, sob fluxo constante de nitrogênio, variando-se a temperatura entre 450 C a 550 C, a quantidade de PEAD no meio reacional foi de 0,2 a 0,6 g, e a quantidade de catalisador foi de zero a 0,06 g, mantendo-se fixa a quantidade de gasóleo em 2 g. Foram efetuadas as caracterizações física e química do gasóleo, polietileno pós-uso e do catalisador. Como resultado, obteve-se a produção de 87% de fração de óleo diesel em duas condições diferentes: (a) 550 0C de temperatura sem catalisador; (b) 500 0C de temperatura e 25% de catalisador FCC. Em ambos os casos, a quantidade de gasóleo pesado e PEAD foram constantes (2 g Gasóleo; 0,2 g PEAD), assim com o tempo de reação de 15 minutos. A fração de óleo diesel obtida neste estudo alcançou o poder calorífico de 44,0 MJ/Kg que é similar ao óleo diesel comercial. É importante ressaltar que em ambos os casos nenhum resíduo foi produzido, sendo uma rota ambientalmente importante para reciclagem de embalagens plásticas contaminadas com óleo lubrificante originárias de postos de serviço, visando à recuperação de ambos conteúdo energético e orgânico dos resíduos de embalagens plásticas pós-uso

Analysis of the retailer value chain segment in five governorates

This study is the third output of the SDC-funded “Improving Employment and Income through Development of Egyptian Aquaculture” (IEIDEAS), a three-year project being jointly implemented by the WorldFish Center and CARE International in Egypt with support from the Ministry of Agriculture and Land Reclamation. The aim of the study is to gather data on the retailer segment of the aquaculture value chain in Egypt, namely on the employment and market conditions of the women fish retailers in the five target governorates. In addition, this study provides a case study in Minya and Fayoum of the current income levels and standards of living of this target group. Finally, the study aims to identify the major problems and obstacles facing these women retailers and suggest some relevant interventions.

Uganda aquaculture value chains: strategic planning mission: summary report

This report presents the findings and recommendations of a strategic planning mission to reevaluate the feasibility of WorldFish implementing a fish value chain research program in Uganda under the CGIAR Research Program on Livestock and Fish (L&F). The over-arching goal of L&F is to increase productivity of small-scale livestock and fish systems so as to increase availability and affordability of meat, milk and fish for poor consumers and, in doing so, to reduce poverty through greater participation by the poor along animal source food value chains. This will be achieved by making a small number of carefully selected animal source food value chains function better, for example by identifying and addressing key constraints and opportunities (from production to consumption), improving institutional arrangements and capacities, and supporting the establishment of enabling pro-poor policy and institutional environments.