Institute of Marine Sciences

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An Account of Sandbank Depositional Modes, Menai Strait, UK
(1992) Nyandwi, Ntahondi
Antimicrobial and Cytotoxicity Activity of Clausena Anisata, Acokanthera Shemperii and Olea Europaea Growing in Tanzania
(2016) Makirita, Winisia E.; Chauka, Leonard J.; Chacha, Musa
Aims: To evaluate antimicrobial and cytotoxicity activities of Clausena anisata, Acokanthera shemperii and Olea europaea against seven Gram negative bacteria and fungal species. Study Design: Bioassay of antimicrobial assay was done using 96-well micro-dilution method. Place and Duration of Study: School of Life Science and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania, from April 2014 to June 2014. Methodology: 96-well micro dilution method was used in antimicrobial assay. Extracts were loaded in the wells of the first row, followed by serial dilution and 50 µl of the bacterial suspensions (0.5 MacFarland standard turbidity) were added in each well. The first concentration which showed no bacterial growth was considered as minimum inhibition concentration. Method developed by Meyer et al 1982 was adopted in cytotoxicity activities. Results: All extracts indicated antibacterial activity on at least three to five of the tested seven bacteria and two fungi species with MIC value ranging 0.7812 - 12.5 mg/mL. The highest activity was demonstrated by Olea europaea leaf methanolic, Acokanthera shemperii stem bark and Clausena anisata twigs ethyl acetate extracts with MIC value of 0.7812 mg/mL against Pseudomonas aeruginosa while the same MIC value was exhibited by Olea europaea stem bark methanol against Proteus mirabilis. However the Olea europaea root methanolic extract inhibited the growth of Pseudomonas aeruginosa and Salmonella kisarawe with MIC value of 0.7812 mg/mL. Olea europaea leaf methanolic and stem bark methanolic which demonstrated high antimicrobial activity were non toxic against brine shrimp larvae with LC50 value of 369.8272 and 226.1566 µg/mL, while Clausena anisata twigs ethyl acetate, Acokanthera shemperii stem bark ethyl acetate and Olea europaea root methanolic extracts were toxic with LC50 value of 6.21276, 67.4179 and 92.3089 µg/mL respectively. Conclusion: This study has unveiled antimicrobial and cytotoxicity properties of Clausena anisata, Acokanthera shemperii and Olea europaea.
Antimicrobial and cytotoxicity Activity of Clausena anisata, Acokanthera shemperii and Olea europaea growing in Tanzania
(European Journal of Medicinal Plants, 2016-04) Makirita W, Makirita W Chauka L and Chacha M
Aims: To evaluate antimicrobial and cytotoxicity activities of Clausena anisata, Acokanthera shemperii and Olea europaea against seven Gram negative bacteria and fungal species. Study Design: Bioassay of antimicrobial assay was done using 96-well micro-dilution method. Place and Duration of Study: School of Life Science and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania, from April 2014 to June 2014. Methodology: 96-well micro dilution method was used in antimicrobial assay. Extracts were loaded in the wells of the first row, followed by serial dilution and 50 μl of the bacterial suspensions (0.5 MacFarland standard turbidity) were added in each well. The first concentration which showed no bacterial growth was considered as minimum inhibition concentration. Method developed by Meyer et al 1982 was adopted in cytotoxicity activities. Results: All extracts indicated antibacterial activity on at least three to five of the tested seven bacteria and two fungi species with MIC value ranging 0.7812 - 12.5 mg/mL. The highest activity
Antimicrobial and cytotoxicity activity of selected Pare folk medicinal plants
(Spatula DD, 2016-05) Godfrey E, Godfrey E Chauka LJ and Chacha M
Aim: The study aimed to evaluate antimicrobial and cytotoxicity of Grewia villosa, Cassia abbreviata and Hoslundia opposita. Methods: Microdilution method and brine shrimp lethality test were employed to evaluate antimicrobial and cytotoxicity of plant extracts. Results: The extracts of G. villosa, C. abbreviata and H. opposita showed different levels of antimicrobial activities on Gram negative bacterial and fungal species tested. The minimum inhibition concentration (MIC) ranges of G. villosa, C. abbreviata and H. opposita extracts were 0.391-25, 0.195-25 and 0.391-25 mg/mL respectively. Cassia abbreviata stem methanolic extracts and roots ethyl acetate extracts exhibited the highest activity with minimum inhibition concentration (MIC) of 0.195 mg/mL against S. typhi and K. oxytoca respectively. At least one of the extract from each plant exhibited a cytotoxicity nature when tested on brine shrimps where the G. villosa stem chloroform extract was the most cytotoxic with fifty percent lethal concentration (LC50) of 48.432 μg/mL. Conclusion: The findings in this study validate the traditional use of G. villosa, C. abbreviata and H. opposita in management of bacterial and fungal infections. Further phytochemical investigations on G. villosa, C. abbreviata and H. opposita growing in Pare Mountains are recommended to contribute to drug development.
Antioxidants activity of the cyanobacterium, Arthrospira (Spirulina) fusiformis cultivated in a low-cost medium
(ACADEMIC JOURNAL, 2018-08) Michael, A.; Kyewalyanga, M.S.; Mtolera, M.S.; Lugomela, C.V.
Spirulina species are known to have a good nutritional profile and antioxidant properties against reactive oxygen species. However, little is known about the antioxidant contents and the scavenging ability of Arthrospira fusiformis, cultivated under various conditions. This study aimed at evaluating the content of antioxidants (total phenols, total flavonoids, β-carotene, and lycopene) and the activity of A.fusiformis produced using low-cost culture (LCMA) and standard culture (Zarrouk) media. The results revealed that A. fusiformis is rich in antioxidants and it possesses high scavenging and chelating activities. Interestingly, the LCMA was superior over the Zarrouk medium as it resulted in spirulina with a higher amount of antioxidants and lower EC50 values. In this context, production of natural antioxidants can be maximized through the use of cost-saving, inorganic culture medium.
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.
Aquacuture in Tanzania
(2006) Michael A., Rice; Mmochi, Aviti J.; Zuberi, Lugazo; Savoce, Rebecca A.
Assessment of Antioxidant Contents and Free Radical-Scavenging Capacity of Chlorella vulgaris Cultivated in Low Cost Media
(MDPI, 2020-12) Mtaki, Kulwa; Kyewalyanga, Margareth Serapio; Mtolera, Matern S.P.
The current study assessed antioxidants contents (total phenolics and total flavanoids, β-carotene and lycopene) present in Chlorella vulgaris (C. vulgaris) cultivated in low cost media and their free radical scavenging activities. Microalgae was cultured using Bold basal medium (BBM) as a control, 5% banana stem compost (BCM) and aquaculture wastewater supplemented with 1.0 g/L NPK (ANM). The free radical scavenging ability was analysed using 1,1-diphenyl-2-picrylhydrazyl assay. Cells grown on BCM resulted in higher (13.73 ± 0.121%) extraction yield than in other media. The phenolic (8.53 ± 0.10 mg/g GAE) and lycopene (0.29 ± 0.008 mg/g) content were highest in cells grown on BCM and BBM, respectively. Microalgae cultured in ANM displayed higher (547.023 ± 34.703 mg/g RE) flavanoid and β-carotene (2.887 ± 0.121 mg/g) content than in other media. Furthermore, cells cultivated in BCM showed highest (97.87 ± 0.088%) scavenging activity than in BBM. These results indicated that the BCM and ANM can be used as alternative to expensive synthetic media for antioxidant production in C. vulgaris.
Assessment of changes in the seagrass-dominated submerged vegetation of tropical Chwaka Bay (Zanzibar) using satellite remote sensing. Estuar Coast Shelf S
(Elsevier, 2006-02-15) Gullström, Martin; Lundén, Bengt Axel; Bodin, Maria; Kangwe, Juma; Öhman, Marcus C.; Mtolera, Matern S. P.; Björk, Mats
Spatial and temporal dynamics of submerged aquatic vegetation (SAV) cover were studied in the relatively pristine and seagrass-dominated area of Chwaka Bay, Zanzibar (Tanzania) by using satellite remote sensing. Through complementary field work the potential of the technique for change detection was verified. The general changes in SAV cover were examined using Landsat images from 1986, 1987, 1998, 2001 and 2003. Two of these images, from 1987 (Landsat TM) and 2003 (Landsat ETM+), were specifically analysed to create a map of the change in SAV cover. Overall, the general distribution of SAV stayed fairly stable over the period investigated, but the result also showed regions where significant alterations, both losses and gains, had occurred between the two years. Based on our findings and anecdotal information from local fishermen and seaweed farmers potential causative factors are discussed. It was concluded that a repeated mapping with satellite remote sensing is a suitable tool to monitor changes of seagrass and seaweed distribution in shallow tropical environments.
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.
Assessment of shoreline changes in the western side of Zanzibar channel using satellite remote sensing
(2003) Shaghude, Yohanna W.; Wanna, K. O.; Lunde, B.
The present study uses a satellite remote sensing approach for assessing coastal sediment dynamics in the western side of the Zanzibar channel, Tanzania. Four Landsat images (1986, 1998, 1999 and 2000) were used for the study. Investigation of the four images revealed that the Ruvu delta north of the river mouth has been growing rapidly, especially between 1986 and 1998, with an annual northward linear growth rate of about 133m year{1 and an areal growth rate of about 1 km2 every 3 years. The study identified a palaeo-shoreline feature that is parallel to the present shoreline and located about 1.9km inland from the present shoreline. An important sediment contributor to river Ruvu is derived from the Uluguru Mountains, a tropical mountainous area located about 200km from the coastline of the Tanzania mainland. The working hypothesis is that either the observed growth of the delta occurred at a gradual rate between 1986 and 1998 or it was mainly an episodic event related to the extreme rainfall events such as the 1997/98 El Nin˜o–Southern Oscillation (ENSO) event, which was associated with extreme rainfall and widespread landslides.
Assessment of shoreline changes in the western side of Zanzibar channel using satellite remote sensing
(Taylor & Francis, 2003) Yohanna W., Shaghude; Wanna, K. O.; Lunde´ N, B.
The present study uses a satellite remote sensing approach for assessing coastal sediment dynamics in the western side of the Zanzibar channel, Tanzania. Four Landsat images (1986, 1998, 1999 and 2000) were used for the study. Investigation of the four images revealed that the Ruvu delta north of the river mouth has been growing rapidly, especially between 1986 and 1998, with an annual northward linear growth rate of about 133m year{1 and an areal growth rate of about 1 km2 every 3 years. The study identified a palaeo-shoreline feature that is parallel to the present shoreline and located about 1.9km inland from the present shoreline. An important sediment contributor to river Ruvu is derived from the Uluguru Mountains, a tropical mountainous area located about 200km from the coastline of the Tanzania mainland. The working hypothesis is that either the observed growth of the delta occurred at a gradual rate between 1986 and 1998 or it was mainly an episodic event related to the extreme rainfall events such as the 1997/98 El Nin˜o–Southern Oscillation (ENSO) event, which was associated with extreme rainfall and widespread landslides.
Beach Sand Supply and Transport at Kunduchi in Tanzania and Bamburi in Kenya
(2012) Shaghude, Yohanna W.; Mburu, J. W.; Uku, Jacqueline; Arthurton, Russell; Nyandwi, Ntahondi; Onganda, H.; Magori, Charles; Sanga, Ignatio
Beach-head erosion of sandy beach plains in eastern Africa threatens tourism-related infrastructure and the livelihoods of beach users. The nature and drivers of physical shoreline change at Kunduchi, Dar es Salaam, and Bamburi, Mombasa, are described with analyses of beach sand transport through the annual monsoon cycle and the provenance and sustainability of the beach sand supply. Time-series records of wind-vectors at Dar es Salaam and Mombasa show similar averaged patterns. Because of the contrasting alignments of these coasts, the net wind-wave driven longshore transport at Kunduchi (trending NNW) is northnorth-westwards, while at Bamburi (trending NNE) there is little net transport. At Bamburi, the beaches are recharged with reef/platform-derived calcium carbonate sand and siliciclastic sand discharged from the hinterland via tidal channels. At Kunduchi, recharge comprises mostly river-borne siliciclastic sand, but riverine sand mining threatens natural replenishment, jeopardising beach maintenance. Eroding beach plain deposits contribute siliciclastic sand at both sites.
Bilko and African capacity development in coastal and marine remote sensing
(ResearchGate, 2012) Byfield, Valborg; Bernard, Stewart; Edwards, Alasdair James; Shaghude, Yohanna W.; Dobson, Malcolm; Louw, Deon C.; Oben, Benedicta M.; Robinson, Ian S.; Whittle, Christo
In much of Africa barriers still exist to the effective use of Earth observation in marine and coastal research and management. To remedy this, the development of data access and processing capacity must go hand in hand with hands-on training in the use of satellite data. The Bilko project has been providing training resources suitable for this for 25 years. In recent years marine scientists from Africa and Europe have been using Bilko to develop lessons based on African examples taken from image data disseminated via GEONETCast in two EC funded projects. The work is part of current efforts to develop MSc level and professional training courses for use in Africa, and shows how the contribution of African experts in the development of new lessons contributes to making these more relevant.
Biogenic Assemblage and Hydrodynamic Settings of the Tidally Dominated Reef Platform Sediments of the Zanzibar Channel
(2002) Shaghude, Yohanna W.; Wannas, Kjell O.
The biogenic assemblage and hydrodynamic settings of the tidally dominated reef platform sediments (TDRPS) east of the Zanzibar channel were investigated in order to characterise the carbonate sediments. Benthic foraminifera were found to be the most important group, both in terms of average abundance (> 60 % by weight) and also in terms of spatial distribution, with common occurrence in all sediments samples. Pelecypods, with an average abundance of 8 % were slightly less widely distributed. The remaining groups occurred at lower average abundance and less frequently in the sediments. Current measurements indicated that the maximum current speed is higher during spring than during neap tides. The direction is phase-dependent with flood tidal current flowing from the northern and southern tips of the island towards Zanzibar town. The ebb current flows in the opposite direction. The geomorphological setting of the carbonate platforms together with the present investigation of the currents and biogenic assemblage of the clastic sediments permits us to subdivide the reef platform area in the Zanzibar Channel into two sub-provinces: the northern and the southern. The northern sub-province contains significantly higher proportion of lithogenic particles, pelecypods, gastropod and ostracods than the southern sub-province. Some samples from the southern subprovince had significantly higher proportion of corals, than those from northern sub-province.
Biomass and nutritive value of Spirulina (Arthrospira fusiformis) cultivated in a cost-effective medium
(SPRINGER NATURE, 2019-12-23) Michael, A.; Kyewalyanga, M.S.; Lugomela, C.V.
Introduction Cultivation of spirulina at commercial-scales relies on analytical grade–based media, which are expensive and so are the product. Purpose This study assessed the biomass, proximate composition, and other useful compounds in Spirulina (Arthrospira fusiformis) produced with a cost-effective culture medium (LCMA), and the results were compared with those from a standard Zarrouk medium–grown spirulina. Methods The LCMA medium was formulated by using a commercial NPK10-20-20 fertilizer as a source of the three major nutrients for spirulina growth, and other three ingredients from Zarrouk medium. The experiment was conducted for 28 days in the glass aquaria under indoor conditions. Standard analytical methods were applied for the determination of proximate composition, chlorophyll, minerals, and vitamins in the spirulina biomass. Result The LCMA medium showed the best growth conditions by accumulating higher chlorophyll content (0.99 ± 0.02%) and dry weight (0.75 ± 0.01 g/100 ml) as well as attaining higher optical density (2.06 at day 15) earlier than the Zarrouk medium. The results of the proximate analysis for spirulina cultured in the LCMA medium were of good quality, with the protein contributing more than 50% of its dry matter. It was further noticed that the LCMA was an ideal medium for optimization of vitamins and some minerals since it recorded a significant amount of most of the analyzed vitamins together with the minerals sodium and potassium compared with the Zarrouk medium. Conclusion It is suggested that LCMA medium could be used as the alternative and cheap medium for maximization of biomass and production of useful biochemical compounds in spirulina species.
Blind to Morphology: Genetic Identifies Several Widespread Ecologically Common Species and Few Endemics among Indo-Pacific Cauliflower Corals (Pocillopora, Scleractinia).
(2013) Pinzón, Jorge H.; Sampayo, Eugenia M.; Cox, Evelyn F.; Chauka, Leonard J.; Chen, Chaolun A.; Voolstra, Christian R.; LaJeunesse, Todd C.
Aim: Using high-resolution genetic markers on samples gathered from across their wide distributional range, we endeavoured to delimit species diversity in reef-building Pocillopora corals. They are common, ecologically important, and widespread throughout the Indo-Pacific, but their phenotypic plasticity in response to environmental conditions and their nearly featureless microskeletal structures confound taxonomic assignments and limit an understanding of their ecology and evolution. Location: Indo-Pacific, Red Sea, Arabian/Persian Gulf. Methods: Sequence analysis of nuclear ribosomal (internal transcribed spacer 2, ITS2) and mitochondrial (open reading frame) loci were combined with population genetic data (seven microsatellite loci) for Pocillopora samples collected throughout the Indo-Pacific, Red Sea and Arabian Gulf, in order to assess the evolutionary divergence, reproductive isolation, frequency of hybridization and geographical distributions of the genus. Results: Between five and eight genetically distinct lineages comparable to species were identified with minimal or no hybridization between them. Colony morphology was generally incongruent with genetics across the full range of sampling, and the total number of species is apparently consistent with lower estimates from competing morphologically based hypotheses (about seven or eight taxa). The most commonly occurring genetic lineages were widely distributed and exhibited high dispersal and gene flow, factors that have probably minimized allopatric speciation. Uniquely among scleractinian genera, this genus contains a monophyletic group of broadcast spawners that evolved recently from an ancestral brooder. Main conclusions: The delineation of species diversity guided by genetics fundamentally advances our understanding of Pocillopora geographical distributions, ecology and evolution. Because traditional diagnostic features of colony and branch morphology are proving to be of limited utility, the identification of Pocillopora species for future ecological and experimental work should rely on genetic characters that will improve research and aid in conservation strategies for these and other reef-building corals, including the detection of real and mistaken endemic populations.
Calibration of Community-based Coral Reef Monitoring Protocols: Tanzanian Case Study
(WIOMSA, 2010) Muhando, Christopher A.
Abstract—Coral reef monitoring (CRM) has been recognised as an important management tool and has consequently been incorporated in Integrated Coastal Area Management (ICAM) programmes in the Western Indian Ocean (WIO). Community-based coral reef monitoring (CB-CRM), which uses simplified procedures suitable for local conditions, was introduced in Tanzania in 1996. Despite its widespread use, the method has not been calibrated and the validity of merging CB-CRM results with those gained using other techniques has not been determined. In this study, CB-CRM protocols adopted by the Tanga Coastal Zone Conservation and Development Programme (TCZCDP) were tested against SCUBA-based coral reef monitoring (SB-CRM) as practiced by the Institute of Marine Sciences, University of Dar es Salaam. Calibration showed no significant differences in measuring percent cover of live hard corals, sponges, dead corals and substrata (non-biotic cover). However, CB-CRM monitors recorded higher soft coral and lower fleshy algal cover. Larger differences were observed in deeper (>6 m) transects. Counts of sea cucumbers, clams, gastropods and bivalves categories were not significantly different. However, CB-CRM underestimated the abundance of sea urchins, starfish and younger macro-invertebrates in crevices or under overhangs. There were no differences in the identification of reef fish categories but CB-CRM recorded slightly higher reef fish densities than SB-CRM. If properly trained, CB-CRM monitors can generate results that are comparable to those obtained from SB-CRM on shallow reefs. Although a powerful tool which engenders community involvement and a sense of ownership in the sustainable use of coastal resources, CB-CRM has limitations of which managers need to be aware.
Co-culture of sea cucumber Holothuria scabra and red seaweed Kappaphycus striatum
(John Wiley & Sons Ltd, 2014) Beltran-Gutierrez, Marisol; Ferse, Sebastian C.A.; Kunzmann, Andreas; Stead, Selina M.; Msuya, Flower E.; Hoffmeister, Thomas S.; Slater, Matthew J.
Commercially valuable sea cucumbers are potential co-culture species in tropical lagoon environments, where they may be integrated into established aquaculture areas used for seaweed farming. In the current study, wild-caught juvenile sea cucumbers, Holothuria scabra, and red seaweed Kappaphycus striatum were co-cultured on Zanzibar, United Republic of Tanzania. Sea cucumbers (97 g 31 SD, n = 52) were cultured in mesh enclosures at initial cage stocking densities of 124 21 SD and 218 16 SD g m 2 under seaweed culture lines. Over 83 days, individual growth rate (1.6 g d 1 0.2 SD) of sea cucumbers at low stocking density was significantly higher (v2 = 8.292, d.f. = 1, P = 0.004) than at high-stocking density (0.9 g d 1 0.1 SD). Seaweed individual growth rates [6.27 ( 0.3 SE) g d 1] were highest in co-culture with sea cucumber at low density but did not differ significantly from high sea cucumber density or seaweed monoculture treatments (v2 = 3.0885, d.f. = 2, P = 0.2135). Seaweed growth varied significantly (v2 = 35.6, d.f. = 2, P < 0.0001) with sampling period, with the final sampling period resulting in the highest growth rate. Growth performance for seaweed and sea cucumbers (v2 = 3.089, d.f. = 2, P = 0.21 and v2 = 0.08, d.f. = 1, P = 0.777 respectively), did not differ significantly between monoculture and co-culture treatments, yet growth in co-culture was comparable with that reported for existing commercial monoculture. Results indicate H. scabra is a highly viable candidate species for lagoon co-culture with seaweed. Co-culture offers a more efficient use of limited coastal space over monoculture and is recommended as a potential coastal livelihood option for lagoon farmers in tropical regions.
Coastal Tanzania, a New Home to the Living Coelacanth: An Oceanographic Analysis
(2006) Nyandwi, Ntahondi
Coelacanth is no longer a new fish in Tanzania. After it was first discovered in September 2003 off Kilwa Masoko in southern Tanzania and with awareness campaigns, fishermen have reported further landings since, mostly in Tanga, northern Tanzania at Kigombe village. Analysis of habitat conditions suitable for the coelacanth indicates that the oceanography may just be right for the fish to have a permanent residence as opposed to the theory of drifters from a natural home elsewhere. At one time three specimens were captured together in the same net indicating that they formed a group. Oceanographic studies of the habitat in Tanga suggest that there could well be a resident population supported by existence of sharp slopes and steps. Caves in which the fish hides might be present at about 150 m depth where suitable temperatures of about 21°C are found.

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