Digital library

  • Scientist fear that the largest and most prized species of the hardy 'opihi a uniquely Hawaiian delicacy may be essentially extinct on O'ahu, and the popluation of other limpets statewide is also on the decline. "Pupu" in Hawaiian means "snail" and in modern times it is used to mean hors d'oeuvres. Opihi were the most favored pupu traditionally.

    Author(s): Harry Ako, Nhan Hua
  • This overview examines the status and trends of seafood production, and the positive and negative impacts of aquaculture on biodiversity conservation. Capture fisheries have been stabilized at about 90 million metric tons since the late 1980s, whereas aquaculture increased from 12 metric tons in 1985 to 45 metric tons by 2004. Aquaculture includes species at any trophic level that are grown for domestic consumption or export.

    Aquaculture has some positive impacts on biodiversity; for example, cultured seafood can reduce pressure on overexploited wild stocks, stocked organisms may enhance depleted stocks, aquaculture often boosts natural production and species diversity, and employment in aquaculture may replace more destructive resource uses. On the negative side, species that escape from aquaculture can become invasive in areas where they are nonnative, effluents from aquaculture can cause eutrophication, ecologically sensitive land may be converted for aquaculture use, aquaculture species may consume increasingly scarce fish meal, and aquaculture species may transmit diseases to wild fish. Most likely, aquaculture will continue to grow at significant rates through 2025, and will remain the most rapidly increasing food production system.

    Author(s): JAMES S. DIANA
  • Chinese aquaculture has employed a balanced ecosystem approach for freshwater aquaculture for several thousand years. Utilizing species that feed at different levels of the food web has permitted China to have the largest freshwater aquaculture production in the world. This production has proved to be sustainable in the long run because there is balance in this system. This concept is just starting to be thought of for broader aquaculture, including marine operations at sea or on land, and fishery communities around the world.

    The National Oceanic and Atmospheric Administration has developed a Sustainable Fisheries Implementation Plan that recognizes three key elements - fisheries, aquaculture and coastal communities - for obtaining sustained production of seafood in the United States. The concepts of carrying capacity for biological activities in  a hydrographic system; ecological balance between primary producers, primary and secondary consumers; and nutrient flows in ecosystems are essential elements for the future development of world aquaculture and fisheries.

    This chapter documents the present status of selected polyculture systems being employed by the aquaculture industry, provides examples of balanced ecosystem approaches to aquaculture and fisheries, and examines the question of how to develop models for maximizing the production of seafood through fisheries and aquaculture working in harmony to minimize environmental impacts.

    Author(s): James P. McVey, Robert R. Stickney, Charles Yarish, Thierry Chopin
  • Artificial seawater prepared with simplified recipes was found suitable for maintaining seaweeds of commercial importance under laboratory conditions. The suitability of this artificial seawater formulation studied by gain or loss of wet weight of seaweeds incubated, showed 15.5% increase in specific growth rate in the case of Gracilaria corticata and 18% increase in the case of Ulva lactuca. However, Gracilaria edulis showed 14% decrease over the control. Physicochemical characteristics of artificial seawater were compared with these of natural seawater.

    Author(s): Kaladharan, P
  • Poverty, hunger and malnutrition affect millions of people across the globe; of these, 25 percent live in sub-Saharan Africa. The challenge is to find suitable and  sustainable technologies which ensure them physical, social and economic access to  sufficient, safe and nutritious food at all times: a situation referred to as food security.  Many scholars, researchers, development agencies and policy-makers argue that  aquaculture, the farming of marine organisms including fish, contributes to food security in many parts of the world including sub-Saharan Africa. A range of  methodologies exist which assess the prevalence and extent of food insecurity. However, little is known about the extent to which aquaculture contributes to alleviating poverty and hunger. 

    This study surveys different methods which could be used to determine the contribution of aquaculture to improving food security. It focuses on four main essential components of food security, namely: stability of food supply, increased availability of food, improved access to supplies and more effective food utilization. Findings indicate that physical, dietary and economic indicators are widely used to achieve this goal. However, because of the complexity and extent of global food insecurity, it is unlikely that, of the methodologies surveyed, a single one can ever accurately quantify the contribution of a given technology, such as aquaculture, to food security. Further research is needed to address this issue. Perhaps a combination of indicators currently used into a methodology could be a starting point.

    Author(s): Louise Cunningham
  • Major progress has been made in the past decade towards understanding of the biosynthesis of red carotenoid astaxanthin and its roles in stress response while exploiting microalgae-based astaxanthin as a potent antioxidant for human health and as a coloring agent for aquaculture applications. In this review, astaxanthin-producing green microalgae are briefly summarized with Haematococcus pluvialis and Chlorella zofingiensis recognized to be the most popular astaxanthin-producers. Two distinct pathways for astaxanthin synthesis along with associated cellular, physiological, and biochemical changes are elucidated using H. pluvialis and C. zofingiensis as the model systems. Interactions between astaxanthin biosynthesis and photosynthesis, fatty acid biosynthesis and enzymatic defense systems are described in the context of multiple lines of defense mechanisms working in concert against photooxidative stress. Major pros and cons of mass cultivation of H. pluvialis and C. zofingiensis in phototrophic, heterotrophic, and mixotrophic culture modes are analyzed. Recent progress in genetic engineering of plants and microalgae for astaxanthin production is presented. Future advancement in microalgal astaxanthin research will depend largely on genome sequencing of H. pluvialis and C. zofingiensis and genetic toolbox development. Continuous effort along the heterotrophic-phototrophic culture mode could lead to major expansion of the microalgal astaxanthin industry.

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  • This report – Avoiding Future Famines: Strengthening the Ecological Basis of Food Security through  Sustainable Food Systems - has been a unique collaboration of 12 leading scientists and experts involved in world food systems including marine and inland fisheries.

    The institutions involved include the UN Environment Programme, the International Fund  for Agricultural Development, the Food and Agricultural Organisation of the United Nations,  the World Bank, the World Food Programme and the World Resources Institute. The report provides  detailed analysis of the many factors threatening the world’s food supplies and its ability to continue to generate calories and proteins in the 21st century including from fisheries. Yet it also provides a series of forward-looking recommendations and remedies to the many grim scenarios that often accompany the food security debate.

     

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  • A story ran in the August 4, 1972 issue of the Portland Press Herald with the headline: “A Future for Seaweed?” The answer is yes. The story was about a young entrepreneur,Robert Morse, who started a seaweed processing

    business, the Samoset Algae Co., in 1971.

    Author(s):
  • In Chile, Bio Architecture Lab broke ground on an experimental pilot facility producing ethanol from Macrocystis pyrifera (brown seaweed): to date, it is believed that only BAL's technology can metabolize all the sugars in the feedstock, which contains up to 60 percent fermentable carbonhydrates, has no lignin, doens not require arable land use or freshwater to grow.

    Author(s):
  • A PDF Power Point on "Big Island Abalone- yesterday, today, and tomorrow".

    Author(s): Celilia Viljoen

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