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Current Status of Dominant Pelagic Fish Species Caught by Purse Seine in the Eastern Sulu Sea and the Basilan Strait
Get PDFData collection was conducted in four (4) pre-identified fish landing sites in Zamboanga City. Sampling was conducted every other two days of the month with the third day as a rest day. The strategies used included interviews with fishers and/or boat captains to determine fishing grounds, type of gear used, total catch, and the number of fishing days. Two data collectors per site determine the species, length (total length if small, and fork length on larger fish), and the weight measurements from the one kilo of samples extracted from the total catch. Results show that the CPUE for the whole commercial fisheries subsector averaged 10,890.5 kg/day while the purse seine, which is the most prevalent gear employed, had a higher average CPUE of 14,142 kg/day. Its monthly CPUE was highest in April at 19,800.28 kg/day and lowest in December at 9,624.83 kg/day. The total catch of the commercial subsector for 2013 was 22,855,452.85 kg with April registering the highest at 4,116,650.9 kg and lowest in December at 313,980 kg. Overall, Sardinella lemuru constituted 45.89% of the total commercial sector production for 2013, followed by Amblygaster sirm at 13.19%, Selar crumenophthalmus at 8.93%, Rastrelliger kanagurta at 8.81% and Decapterus macrosomaat 8.17%. The most exploited species was Decapterus macrosoma caught by Purse Seine with an E value of 0.71, followed by Sardinella lemuru with 0.59, Amblygaster sirm with 0.57, and Rastrelliger kanagurta with 0.51. The species Selar crumenophthalmus has the lowest E value at 0.38. The maximum length (Lmax) of S. lemuru, A. sirm, R. kanagurta, and D. macrosoma are much higher than the published values of length at first maturity of subject species. Decapterus macrosoma, S. lemuru, A. sirm, and R. kanagurta all have higher fishing mortality than natural mortality suggestive of overexploitation. Amblygaster sirm and Rastrelliger kanagurta caught by purse seine were both captured before maturity with L25 values of 15.0 cms and 19.0 cm respectively while Sardinella lemuru and Decapterus macrosoma were already matured when captured with values of 15.0 cm and 19.0 cm, respectively. Fishing pressure on the most dominant species, S. lemuru, is high and its maximum length has gone down by as much as 23% over the past decade
PICES Press, Vol. 26, No. 2, Summer 2018
Get PDF2018 Inter-sessional Science Board Meeting. 2018 Pacific Ecology and Evolution Conference. Applying global experiences to regional assessments: A workshop on the Protection of Vulnerable Marine Ecosystems. Activities of the joint PICES/ICES/PAME WG on an Integrated Ecosystem Assessment for the Central Arctic Ocean. In memoriam: Dr. Mary N. Arai. Highlights from the FUTURE SSC’s 4th Inter-sessional Meeting. PICES Interns. A new PICES MAFF-sponsored project: Building capacity for coastal monitoring by small-scale fishers. Scientists from PICES and Mexico meet to discuss closer ties in North Pacific research. An International Symposium on “Understanding changes in transitional areas of the Pacific”. The 4th International Symposium on “The effects of climate change on the world’s oceans”. ECCWO-4 Workshop on “Communicating and responding to climate change”. ECCWO-4 Workshop on “Advances in Earth System Models (ESMs) for marine applications”. ECCWO-4 Workshop on “Exploring potential ocean-based solutions to climate change impacts on marine biodiversity and ecosystem services”. ECCWO-4 Workshop on “Climate change adaptation of fisheries and aquaculture: examples of field projects supporting countries and communities”. ECCWO-4 Workshop on “Climate change and fishing communities: Interactions with environmental conservation, sustainable livelihoods and food security”. ECCWO-4 Workshop on “Utilizing bioenergetics measurements and modeling to evaluate climate change effects on marine species and ecosystems”. ECCWO-4 Workshop on “What do seabirds reveal about the effects of climate change on the world’s oceans?”. ECCWO-4 Workshop on “Connecting climate, ocean and ecosystem observation – Ocean observation futures”. ECCWO-4 Workshop on “Vulnerability of Low Elevated Coastal Zones (LECZ) to SLR in changing oceans”. ECCWO-4 Workshop on “Quantifying thresholds in driver-response relationships to identify reference points”. The Bering Sea: Current status and recent trends. The Northeast Pacific: Current status and recent trends. The western North Pacific during the 2017/2018 cold season. Topic sessions and workshops at PICES-2018. Progress in Oceanography Special Commemorative Issue
The hydrochemical study of Chitgar Lake
Get PDFThe man-made Lake of the Martyrs of the Persian Gulf (also known as the Chitgar Lake) is located in the northwestern of Tehran and was established in 2012 and field with Kan River water at the same year. The water quality was investigated on 5 sampling site during 2013-2014. Standard methods (APHA, 2005) were used for Analysis of water parameters. The results indicated that the mean monthly temperature of water was 18.4±7.3 °C. The mean monthly EC level was 373±30 µs/cm. The mean monthly total hardness, dissolved oxygen, total phosphorous, total nitrogen, silicate, respectively were 119±5, 7.8±1.2, 0.04±0.01, 2.06±0.41, 9.6±0.5, all as mg/l,. The mean chlorophyll-a was 1.6 ± 0.81 µg/l. All parameters showed no significant differences between stations (P>0.05), while total hardness, chlorophyll-a, Do, total phosphorus and silicate showed monthly significant differences with 95% confidence level. The ratio of total nitrogen to total phosphorus was 51 which indicated phosphorus is limiting factor in eutrophication process. According to Carlson trophic index determined to be oltraoligotroph (TSI<40). The result indicated that changes in nutrient concentration is under biological activity influence
The survey on aquaculture capacity of Ghar-Khatlo dam reservoir in Zanjan province
Get PDFQhar-khetlu dam reservoir is in the central part of Ijrud city of Zanjan province with a reservoir volume of 500000 and a water volume of 900000 cubic meters, covering an area of 6 hectares and containing 3500 hectares of the watershed in order to control seasonal floods, drinking water in the village, strengthening the aquifers of the area and As a water supply in the dry seasons, 120 hectares of agricultural land was planted for irrigation.Study of this water source with the aim of measuring biological and non-biological factors, determination of aquaculture production and Fish release capacity and fishing capacity for optimal use of fishery management in Zanjan province was done in 2006.The results of hydrochemical analysis of the water of Qharkhetlu dam reservoir showed that the minimum and maximum temperature of water ranged from 4.5 to 26 ° C, the pH of the water was 4.7 to 8.8, the dissolved oxygen was 7.7 to 12.2 mg, the total water hardness fluctuation was 154 194 mg/L and electrical conductivity of 272 to 390 micrometers per square centimeter, the water transparency was 25 to 380 centimeters.In this study, six phytoplankton classes with 31 genera and 3 classes of zooplankton with 14 genera were obtained. The abundance of phytoplanktons was counted from 150,000 to 206,000 per liter, and the average chlorophyll a, 1.10 micrograms, was estimated. The frequency of zooplanktons were 32 to 132 per liter, as well as the mean of 544 per square meter of macrobenthos.By comparing of the physical, chemical and biological factors and also the results of previous studies of this water source, the conditions for the introduction of warm water and cold water fishes including silver carp, big head carp, rainbow trout out and native fishes including species of Barbus and Capoeta genera are suitable. Estimation of Qhar-khetlu dam reservoir production is 80 kg/ha and its production capacity is 484 kg per year
Human rights/sustainable oceans: a fishbowl approach
Get PDFIn overview of the Danish Institute for Human Rights’ international expert meeting on the contribution of human rights to the sustainable development of fisheries. In September 2015, the United Nations General Assembly adopted its resolution, “Transforming our world: the 2030 Agenda for Sustainable Development,” for the overarching goal of poverty eradication and the realization of the human rights of all
Optimization of growth, lipid and chlorophyll contents in Chlorella vulgaris under different conditions of nitrate, phosphate and photoperiod by central composite design (CCD)
Get PDFThe effects of nitrate (750-2250 mg/L), phosphate (20-60 mg/L) and photoperiod (8-24 h) on the growth, chlorophyll content and lipid yield of Chlorella vulgaris were studied using central composite design (CCD) method. The second-order quadratic model was used to predict the effects of input variables on the output responses and the results were verified by F test, ANOVA and regression analyses. Results showed that maximum growth (255.88 ×106 ) as well as highest chlorophyll content (15.34%) were observed at 16 h of light, 1500 mg/L of nitrate and 40 mg/L of phosphate concentration. Also, condition of 24 h of light, 750 mg/L nitrate and 20 mg/L phosphate concentrations resulted in maximum percent of lipid content (17.74%). The optimization of culture condition for simultaneous achievement of highest levels of growth, chlorophyll and lipid content were investigated
The in vivo effect of methyl tert-butyl ether on liver, gills and kidney tissues of Rutilus caspicus
Get PDFThis study was conducted to evaluate histopathological responses in liver, gills and kidney in Rutilus caspicus exposed to concentrations of 50, 100, 150 mg L^-1 of methyl tert-butyl ether, for 7, 14, and 21 days. The experiments were conducted in water temperature of 19±1 °C, dissolved oxygen of 7.6 ± 0.2 mg L^-1 and zero salinity. A total of 156 fish were studied in this experiment. In the first, second and third week of the experiment, three fish were taken randomly from each aquarium. To examine the tissues, the liver, gills and kidney were isolated and prepared for evaluation using standard histological techniques. Tissue damage in the liver includes: blood congestion, congestion of sinusoid, melano macrophage aggregation, hepatocyte hypertrophy, vacuolation, degeneration and cellular necrosis. Gill tissue damage includes: hyperplasia, degeneration lifting, telangiectasis, in secondary lamellae, blood congestion in primary and secondary lamellae, S formation of lamellae, and reduction in length of secondary lamella, lamellar fusion and cellular necrosis. Tissue damage in the kidney includes: tubular shrinkage, blood congestion, melano macrophage aggregation, glomerular shrinkage, cellular necrosis, tubular degeneration, reduction in interstsial cells and interstisial hematopoietic tissue degeneration. The amount of tissue damages in high concentrations of pollutants was high, while gill, liver and kidney in the control group were observed in the normal outline. The results of this study showed that methyl tert-butyl ether (MTBE) can cause damage in vital tissues of R. caspicus and even, eventually lead to death
The effect of different feeding rates and restriction on the growth performance of Clarias gariepinus
Get PDFFish is a primary source of protein for many persons in the world (Rameshguru et al., 2011). However increase population pressure not adequately matched with fish production has caused more demand pressure on the fisheries sector. Hence, there is a need to increased aquaculture production to solve this problem associated with the market demands of fish and fish products (Aydin et al., 2011). The species of high yield potential for aquaculture production in Africa are the Nile tilapia (Oreochromis niloticus), common carp (Cyprinus carpio) and African catfish (Clarias gariepinus) (FAO, 2008). Production of these species has been with the addition of organic manures to pond water so as to stimulate the growth of natural food organism (Robinson and Li, 1999). However, supplementary feeding has become widely practiced in modern aquaculture in the quest for improvingproductivity. Feeding now accounts for above 60% of the total cost of fish production in Africa, hence, determining the viability and profitability of fish farming enterprise (Jamu and Ayinla, 2003). Commercial diets commonly used are very expensive and fed to fish at different self-determined rate and feeding frequencies so as to break even. Fish farmers also prepare on-farm feed using alternative feedstuffs which are locally available, cheap and usually unconventional so as to reduce the cost of production and maximize profit
Synthèse de la production des régions continentales statistiques de juillet 2018
Get PDFLe sous-secteur de la pêche continentale est une composante essentielle de l’activité halieutique et revêt une importance capitale pour l’économie des régions continentales (Source importante de protéine et de revenues). La Pêche continentale est pratiquée aussi bien au niveau des principaux fleuves qu’au niveau des mares et autres plans d’eau aménagés. Elle est une activité artisanale qui cherche à s’améliorer de jour en jour avec l’aide de l’Etat à travers des aménagements d’infrastructure et autres donations et subvention d’équipements.
La Production de la continentale varie d’une région à une autre du fait de la configuration hydrographique, des écosystèmes et du professionnalisme des acteurs
Yemaya, No.58, December 2018
Get PDFYemaya No. 58, dated December 2018, features articles from Kenya, Mexico, India, and an analytical article on gender inequalities in the seafood industry. The editorial comment calls for gender mainstreaming throughout the fisheries sector. The article on Kenya by Irene Ojuok and Philemon Bwanawoy throws light on the new initiatives developing in the context of declining resources in Kenya. Women are entering in new roles along the value chain and they no longer have to engage in jaboya thanks to new income-generating projects. Carmen Pedroza Gutierrez in her article narrates the experience of Alejandra and Maria Elena from Mexico's Lake Chapala and examines how women fishers are excluded from the support net of social security measures or benefits and how vulnerable their life is without any legal recognition. The article from India by Holly Hapke looks at how the mechanization in fishing and retrieving catch using mechanical propulsion led to greater centralization of fish landings and the impact on women fish traders. The centralization of landings has created competition from men fish traders too. Marie Christine Monfort in her article on survey among male and female seafood professionals to express their view about the situation of women in the fishing industry aregue that situations of inequality have bben reported from all parts of the world with the exception of Scandinavia. The seafood professionals from this region rank Denmark, Iceland and Norway at top countries closest to gender equality. In her review of the Cambodian film, Give Woman a Fish, Kyoko Kusakabe describes the challenges women fishers face in Cambodia’s Tonle Sap Lake. The lake supports the 60% of Cambodia’s annual fish catch and livelihood to 1.5 mn people. The film describes how a successful project supported by a women’s group to upgrade their fish processing techniques, introduced savings and helped to diversify livelihoods. A profile of Sonia Medina Matarrita, fisherwoman from Isla Venado, Costa Rica by Vivienne Solis Rivers narrates the story of how under Sonia’s leadership, the Venado Island fishers association got involved in the implementation of responsible fishing in the Marine Responsible Fishing Area of the island. The Milestones column presents the urgent need to guarantee the social protection and safety of workers (women and men) in the sector. The declaration calls our attention to provide professional dignity to fishers’ activity so that it can be considered "decent work", according to the ILO definition. The declaration states that it is necessary to improve the working conditions of women within the sector, fighting against the informality and precariousness of women's work, segregation both horizontally and vertically, the wage gap and barriers that hinder the reconciliation of work, family and personal life. The What's New, Webby? column presents the details of a new women in fisheries project which examines how women contribute to the survival of both fishing families and the fishing industry. The current issue of the Newsletter also carries the ever-popular cartoon strip, Yemaya Mama, reading between the lines. .. Yemaya No. 58, December 2018, can be accessed at: https://www.icsf.net/en/yemaya/article/EN/58.html?limitstart=