Browsing by Author "Jiddawi, Narriman"

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    Aquaculture Research and Development as an Entry-Point and Contributor to Natural Resources and Coastal Management
    (Taylor & Francis, 2010) Crawford, Brian; Celia, Maria; Portella, Maria; Ellis, Simon; Jiddawi, Narriman; Mmochi, Aviti J.; Camacho, Eladio; Dominguez, Guillermo Rodriguez; Rodriguez, Gustavo; Francis, Julius; Leclair, Carlos; Oze, Agnes; Hernandez, Nelvia; Sandoval, Erick; Aarroszewska, Marta; Dabrowski, Konrad
    Integrated coastal management (ICM) is often defined as some variant of the definition provided by Cicin-Sain and Knecht (1998, 11) as “a continuous and dynamic process by which decisions are taken for the sustainable use, development, and protection of coastal and marine areas and resources. ICM acknowledges the interrelationships that exist among coastal and ocean uses and the environments they potentially affect, and is designed to overcome the fragmentation inherent in the sectoral management approach. ICM is multipurpose oriented, it analyzes and addresses implications of development, conflicting uses, and interrelationships between physical processes and human activities, and it promotes linkages and harmonization among sectoral coastal and ocean activities.” Aquaculture is a wide-ranging economic development activity involving culture of marine or brackish water plants, animals, or microorganisms at some point in their life cycle. As such, aquaculture has traditionally occupied a primary place among development activities in coastal areas, and is rapidly expanding to supply protein-rich foods and other products, filling the gaps left by the decline of capture fisheries as the world population continues to grow. Growth is also expected as culture technologies and species development increasingly make new forms of aquaculture, such as off-shore systems, feasible. Aquaculture supplies approximately 47% of the world’s seafood supply and is the fastest growing form of animal husbandry at 6.9% per annum. Per capita production rose from 0.7 kg in 1970 to 7.8 kg in 2006 producing 66.7 million tons of plant and animal material with a value of $85.9 billion (Food and Agriculture Organization [FAO], 2008). Consideration of aquaculture within the context of ICM is critical as both become more important. Changes brought on by climate change will also affect the role of aquaculture along the world’s coasts, major rivers and watersheds. Aquaculture is often regarded primarily in a negative light when considered by coastal management programs, often ignored completely. Aquaculture is also often viewed as an “industry” responsible for habitat destruction, competing with other economic activities, displacing local peoples and their traditional occupations, and as an inefficient use of inputs and resources. Use of the term “industry” is misleading as very few forms of aquaculture are sufficiently large and consolidate, and geographically or structurally coherent enough to merit this term. Shrimp or salmon culture may merit this designation. Most aquaculture is conducted on a small to medium scale. FAO estimates that 80% of world aquaculture production is produced by smallholders (Subasinghe & Phillips, 2005). In fact, the lack of cohesiveness and sectoral organization is a major challenge for inclusion in natural resources management programs. Social and economic impacts are also commonly alleged to occur. This is a more problematic topic than the issue of environmental impacts since social or economic inequities or injustices are rarely well documented and are difficult to distinguish from similar issues occurring throughout a particular nation’s socioeconomic milieu. The environmental, social, and economic costs and benefits of aquaculture are highly nuanced and variable depending on which region, species, and form of aquaculture is practiced. The authors’ intention is not to debate whether or not impacts occur, to what extent or which sectors within aquaculture Downloaded By: [University of Rhode Island] At: 17:59 1 June 2010 240 M.
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    Assessment of Regional and Local Biodiversity in Tropical and Subtropical Coastal Habitats in the East African Marine Ecoregion
    (Springer, 2011) Barnes, Natalie; Bamber, Roger N.; Bennell, Graham; Cornelius, Nils; Glassom, David; Henderson, Sophie C. D.; Jiddawi, Narriman; Lee, Christine N. W.; Macia, Adriano; Msangameno, Daudi J.; Paula, José; Yahya, Saleh; Ferrero, Timothy J.
    The transboundary networks of Marine Protected Areas (MPAs) project, TRANSMAP, assessed local turnover and regional biodiversity across the East African Marine Ecoregion, where inter-governmental co-operation has been working to connect local MPAs. The benthic fauna in the three most dominant habitats on this coastline— beaches, mangroves and seagrasses—were studied in two Regions (Northern Region, 10–13S; Southern Region, 25–28S). Meiofaunal taxa were used as the model faunal group owing to their diversity and abundance across habitat types and environmental conditions. Meiofaunal abundance averaged 2,500 individuals 10 cm-2 and was generally higher in mangrove and seagrass sediments than on the beaches, and was significantly different between habitats 9 Regions. In total, 18 taxa were recorded with highest diversity in the beach samples. Diversity indices and assemblage structure were signifi- cantly different between habitats, but also Regions. Specific granulometric 1U size classes,shore-height and number of rain days were the factors most significantly correlating with the observed assemblage patterns. Additionally, the size of a MPA and latitude (which correlated with MPA age, but not number of rain days), were the factors fitting best with meiofaunal assemblage patterns across the beaches, the habitat for which the most comprehensive data were generated. Sample diversity was higher in the Southern Region, and although within- and across-habitats diversity were similar across the Regions, the two Regions appeared to provide complementary habitats and supported different assemblages. Within the Regions, beaches (the only habitat for which more than one location was sampled) were significantly different between Locations, supporting the establishment of multiple protected locations of the same habitat within each transboundary MPA.
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    Design and preliminary results of an integrated mariculture pond system (IMPS) at Makoba, Zanzibar,Tanzania
    (National Centre for Mariculture, 2001) Mmochi, Aviti J.; Mozes, N; Kite-Powell, H.L.; Dubi, Alfonse M.; Gordin, H; Jiddawi, Narriman; Kissil, G; Msuya, Flower E.; Mwangamilo, J
    Mariculture development in Zanzibar Island, Tanzania, is limited by the lack of appropriate technology for local conditions and cost-effective solutions for preventing nutrient enrichment of the marine environment. An integrated mariculture pond system (IMPS) concept originally developed in Israel is considered as a possible model for mariculture development in Zanzibar. An experimental IMPS has been established near the estuary of Kiwani Creek at Makoba on the west coast of the island. Water supply is provided by a reservoir fed by tidal fluctuations in the creek. The experimental system consists of six ponds of 170m3 each, for the culture of fish, shellfish and seaweed. The ponds were stocked during June and July 1998 with 4000 fingerlings of rabbitfish (Siganus sp.) and with different species of shellfish and seaweed. Water quality parameters in the ponds, such as temperature, oxygen and salinity, were kept within acceptable limits by a periodic water supply. Fish were fed daily with a diet developed for this project. Preliminary results indicate reasonable growth of the fish but also mortality of fish, shellfish and seaweed.
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    Single and joint effects of regional‑ and local‑scale variables on tropical seagrass fish assemblages
    (Spinger, 2014-08-14) Aller, Elisa Alonso; Maarse, Floriaan K. J. E.; Gren, Michaela; Nordlund, Lina Mtwana; Jiddawi, Narriman; Eklöf, Johan S.
    Seagrass beds are highly important for tropi- cal ecosystems by supporting abundant and diverse fish assemblages that form the basis for artisanal fisheries. although a number of local- and regional-scale variables are known to influence the abundance, diversity and assemblage structure of seagrass-associated fish assemblages, few studies have evaluated the relative and joint (interacting) influences of variables, especially those acting at different scales. Here, we examined the relative importance of local- and regional-scale factors structuring seagrass-associated fish assemblages, using a field survey in six seagrass (Thalassodendron ciliatum) areas around Unguja Island (Zanzibar, Tanzania). Fish density and assemblage structure were mostly affected by two regional-scale variables; distance to coral reefs, which positively affected fish density, and level of human development, which negatively affected fish density. On the local scale, seagrass biomass had a positive (but weaker) influence on fish density. However, the positive effect of seagrass biomass decreased with increasing level of human development. In summary, our results highlight the importance of assessing how multiple local and regional variables, alone and together, influence fish communities, in order to improve management of seagrass ecosystems and their services.
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    Wild Black-lip Pearl Oyster (Pinctada margaritifera) Spat Collection in Tanzania
    (WIOMSA, 2011) Ishengoma, Edson; Jiddawi, Narriman; Tamatamah, Rashid; Mmochi, Aviti J.
    Abstract—Pearl farming is a growing aquaculture activity in Tanzania but requires sufficient young pearl oysters to make it feasible. Collection of spat in the wild is the most viable way of doing this and was tested to establish whether it would yield sufficient juvenile pearl oysters to support an industry. A total of 4263 Pinctada margaritifera spat were collected over a year at sites considered suitable for spat collection: Bweleo and Nyamanzi on Zanzibar, and Tawalani in Northern Tanzania. Spat “yield” exhibited seasonal variations at these sites in a pattern similar in annual trend at Tawalani and Bweleo but different at Nyamanzi. Generally, the dry season (June-November) yielded a higher number of spat than the wet season (December-May). During the dry season, Tawalani, Bweleo and Nyamanzi produced 877, 942 and 1176 P. margaritifera spat respectively, while, during the wet season, these numbers were 503, 730 and 35. A few other pearl oysters such as Pteria penguin were inadvertently collected at Nyamanzi during the study. Three different types of spat collectors were used during the study, comprising coconut shells, spat bags and rubber tiles. There was significant variation in the number of spat collected on these materials (P < 0.01). The yield was always greater on spat bags and rubber tiles than on coconut shells. The study showed that it is possible to collect sufficient numbers of wild spat for the culture of black-lip pearl oysters at some sites along the coast of Tanzania