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Belize: access rights, free to move
Get PDFBelize, a pioneer in fisheries conservation, has become the first country to adopt a national, multispecies territorial user rights programm
Africa: SSF guidelines, co-operate to move forward
Get PDFAn Africa Workshop focused on creating awareness about the SSF Guidelines, lobbying for their implementation, and aligning them with national fisheries policie
AKTEA network: perils and prospects
Get PDFTwenty years of organising by women in Europe’s fisheries have led to important gains, challenges and opportunities
Effects of essential oils of Satureja bachtiarica and Nigella sativa on the efficacy of lactococcosis vaccine in rainbow trout (Oncorhynchus mykiss)
Get PDFLactococcosis has been defined as acute septicaemia, which causes economic losses in farmed fish, especially in rainbow trout. This study was done to evaluate the effects of the essential oils of Satureja bachtiarica and Nigella sativa on the efficacy of lactococcosis vaccine in rainbow trout. A total number of 270 fishes with a mean weight of 120 g were obtained; they were randomly divided into nine groups, each with three replicates, after two weeks of adaptation. The groups were: no injection group, vaccine only group, DMSO injection group, vaccine with 50, 100, and 200 micrograms Intraperitoneal injection (IP) injection. Two, four, and six weeks after vaccination, serological and haematological parameters were evaluated. In the sixth week, 1.7×10^7 cfu as LD50 96 hrs of Lactococcus garvieae were IP injected and the relative survival percentage was calculated. The results indicated that N. sativa essence is effective on the leukocyte population as the highest number of leukocytes were found in fish receiving high concentration of N. sativa. The relative survival rate of the studied fish decreased with decreasing concentrations of the N. sativa essential oil concentration, with a significant difference with control groups (p<0.05). However, using S. bachtiarica was not significantly effective on the relative survival rate of fish. The results of this study indicated that N. sativa essential oil can be used as adjuvant for L. garvieae vaccine, since it resulted in increasing leukocytes and the relative survival rate although S. bachtiarica was not effective on immune parameters of the studied fish
Age, growth and spawning season of Luciobarbus esocinus Heckel, 1843 in Gamasiab River, Iran
Get PDFIn the current paper reproductive strategy and growth rates of Luciobarbus esocinus were investigated from 2010 to 2012, in Gamasiab River, Kermanshah, Iran. Samples were collected seasonally by gillnet and electro-fisher device. Sex ratio was evaluated from 162 individuals and the percentage of male and female individuals were 54.76% and 45.24% respectively. Age structure was distributed between I and V and most frequency numbers for males and females belonged to II and IV age group, respectively. Length-weight relationship was computed as W=8E-05TL^2.6546 for all individuals. Mean total length and weight was 333.82±13.10 mm and 297.67±4.85 g for males, and 371.5±21.17 mm and 307.85±7.64 g for females. The von-Bertalanffy growth models of L. esocinus were described as Lt =357.14×[1-e^(-0.77×(t-0.090))] for males, Lt =367.02×[1-e^(-0.78×(t–0.094))] for females and Lt =363.57×[1-e^(-0.76×(t –0.087))] for both sexes. Results indicated that growth factors were highly similar in spring, summer and winter. CDA analysis revealed that the total and gonad weight are the main factors in discriminant analysis. The highest GSI values were found in spring for females and winter for males, however, it decreased rapidly after spring in females. Maximum growth rates were observed in early ages (I-II) and depleted with ages. K value and L∞ were determined as 0.77±0.09 Y^-1 and 357.14±10.38 mm for males and 0.78±0.24 Y^-1 and 367.02±24.15 mm for females, respectively. In conclusion this study provided basic information for stock assessment and management of L. esocinus in Gamasiab Reservoir
Evaluation of ecological status of the Persian Gulf inshore waters (Hormozgan rocky bottoms) using macrophytic communities and a macroalgae biological index, EEI
Get PDFMarine benthic macrophytes (seaweed and seagrasses) are key structural and functional components of some of the most productive ecosystems of the world. They absorb nutrients through their surface directly from the marine environment and thus they are very important biological elements for the estimation of ecological status, representing reliable indicators of coastal waters. The aim of this study was to assess the ecological status and trophic level of Hormozgan rocky bottoms according to Ecological Evaluation Index (EEI). Sampling was done bi-monthly at seven stations at the intertidal rocky shores, west of Hormozgan Province. In this study a total of 63 species were identified, of which 15 species from seven genera belonged to green algae; 16 species from five genera belonged to brown algae; and 32 species from nine genera belonged to red algae. Coverage data of macroalgae and EEI indicate a high level of eutrophication for Saieh khosh, and Bostaneh. They are classified as zones with bad and poor ecological status, respectively. Also it has been proved that concentrations of biogenic elements and phytoplankton blooming are higher in these zones. The best values of the estimated metrics at Tahooneh and Michaeil could be explained with the good ecological conditions in those zones and the absence of pollution sources close to those transects. The values of abundance of macroalgae and EEI indicate moderate ecological conditions for Koohin, Lengeh and Chirooieh
Value Chain Analysis of Marine Ornamental Fish Industry in the Philippines
Get PDFThe Philippines is a major supplier of marine ornamental fish in the world but the understanding of the overall local industry is limited. This study assessed the marine ornamental fish industry in the Philippines using the value chain analysis approach aimed to describe the market chain and key actors, species collected and traded, cost distribution in each of the stakeholders involved, and value addition across actors. Survey interview using purposive sampling was conducted in major collection areas in the country and data gathered was analyzed through a mixed-methods approach and validated by focus group discussions. The results identified the actors in the chain as diver-gatherer, middleman-trader, and exporter. There were 1,431 stakeholders directly dependent on the industry. The annual trade approximately involved a total of 8,554,729 pieces comprised of 1,200 marine species belonging to 144 families contributing PHP 235,496,302.50 to the country’s economy. The bulk of the supply came from Region 4A (61.06%), Region 3 (26.63%), and Region 7 (5.32%). The value chain of the industry was mapped out, revealing a gross value addition of PHP 88.27 per marine ornamental fish. Cost-return analysis showed the last node actors having the highest monthly net return while the lowest in the first node actors. Appropriate programs, policy, and institutional reforms needed to maximize the benefits of the business across key actors and ensure the sustainability of fish resources in the wild were presented
The Blue Swimming Crab Fishers and Fishing Practices in Leyte and Samar, Philippines
Get PDFBlue swimming crab (BSC) industry contributes considerably to the region’s economy. Despite the extensive harvesting and marketing activities, there is no information on the people who make a living out of the BSC resource. This study provides suggestions to improve the management of BSC fishery by looking into the crabbers’ socio-demographic profile, crabbing gears, crabbing practices, and awareness of regulatory measures regarding BSC fishery management. Semi-structured interviews were conducted from April to August 2014 in selected crabbing municipalities in five major fishing grounds of Eastern Visayas. Generally, the income of the crabbers and their family is way below the poverty threshold indicated for Eastern Visayas. This condition is aggravated by the lack of formal education among the crabbers and their members, which limits them from engaging in other livelihood opportunities. The marginal contribution from other livelihood sources to the household income is still insufficient to support other needs, particularly education. To increase the daily catch, crabbers resorted to unsustainable and destructive crabbing practices, which depletes further the resources. To address these issues, LGUs in partnership with other concerned organizations should formulate and implement programs and projects that will alleviate the living conditions of the crabbers. Moreover, the LGUs should implement national plans along with local legislation to ensure the regulation of BSC catching and selling. Crabbers must practice sustainable, cost-effective, and non-destructive crabbing activity to improve BSC production. Further studies into the biology, seasonality, and stock assessment are needed to craft appropriate science-based management framework
Determination of effective parameters on growth and bloom forming of Cochlodinium polykrikoides
Get PDFAlthough the most alga blooms usually provide positive impacts on marine ecosystems, but blooming of certain species of algae may also have negative impacts which evidence suggests that over the past few decades the frequency and duration of Harmful Algal Blooms (HABs) have been increasing both nationally and worldwide. Harmful algal blooms of Cochlodinium polykrikoides in the Persian Gulf and Oman Sea were first observed in 2008. In order to provide optimum growth and bloom forming, C. polykrikoides cells were sampled during the bloom conditions in the coastal waters of Bandar Abbass, Qeshm and Hourmoz Islands from March 2012 to June 2015. After sampling, the samples transferred to Persian Gulf and Oman Sea Ecological Research Institute phytoplankton Lab and adapted to filtered seawater. In Phycolab, they isolated and purified by positive phototropism characteristic of species to light. They were grown in modified media culture at different salinities (30, 32 and 35ppt), temperatures (20, 23, 26 and 28ºC) and intensities (35, 70 and 90 µmol m^-2s^-1). During this study 3 Dinoflagellates species were identified in Hormozgan Coastal waters. The first species was Noctiluca scintillans. This species was alive in F/4 media culture and under the 32ppt salinity, 25°C temperature, and an 11h light: 13h dark photoperiod regime only for 4 months. The second species was Protoperidinium quinquecorne and produced temporal blooms that could not be isolated under usual and modified media cultures. The last Dinoflagellates species that caused spreading blooms in Hormozgan Coastal waters and could be possible to isolate was Cochlodinium polykrikoides. The results clearly showed that the best media culture for growth of this species is A2 and the highest alga biomass was obtained following culture under the 32ppt salinity, 26°C temperature, and under an 11h light: 13h dark photoperiod regime at a light intensity of 90 µmol m^-2s^-1 provided by cool white fluorescent tubes. Maximum cell density of C. polykrikoides in a 5 liter Erlenmeyer for 12 days reached to 1.6 × 106 cell L^−1 with 2-12 and occasionally to 16 cells chain. Based on the results from the present study, providing suitable media culture and physical condition, bloom forming of C. polykrikoides start from day 8 and will be continued until day 24