Central Marine Fisheries Research Institute

Cochin, India

Central Marine Fisheries Research Institute

Cochin, India
Time filter
Source Type

News Article | January 31, 2017
Site: www.theguardian.com

The Bay of Bengal’s basin contains some of the most populous regions of the earth. No less than a quarter of the world’s population is concentrated in the eight countries that border the bay1. Approximately 200 million people live along the Bay of Bengal’s coasts and of these a major proportion are partially or wholly dependent on its fisheries2. For the majority of those who depend on it, the Bay of Bengal can provide no more than a meagre living: 61% of India’s fisherfolk already live below the poverty line. Yet the numbers dependent on fisheries are only likely to grow in years to come, partly because of climate change. In southern India drought and water scarcity have already induced tens of thousands of farmers to join the fishing fleet3. Rising sea levels are also likely to drive many displaced people into the fishing industry. But the fisheries of the Bay of Bengal have been under pressure for decades and are now severely depleted4. Many once-abundant species have all but disappeared. Particularly badly affected are the species at the top of the food chain. The bay was once feared by sailors for its man-eating sharks; they are now rare in these waters. Other apex predators like grouper, croaker and rays have also been badly hit. Catches now consist mainly of species like sardines, which are at the bottom of the marine food web5. Good intentions have played no small part in creating the current situation. In the 1960s, western aid agencies encouraged the growth of trawling in India, so that fishermen could profit from the demand for prawns in foreign markets. This led to a “pink gold rush”, in which prawns were trawled with fine mesh nets that were dragged along the sea floor. But along with hauls of “pink gold” these nets also scooped up whole seafloor ecosystems as well as vulnerable species like turtles, dolphins, sea snakes, rays and sharks. These were once called bycatch, and were largely discarded. Today the collateral damage of the trawling industry is processed and sold to the fast-growing poultry and aquaculture industries of the region6. In effect, the processes that sustain the Bay of Bengal’s fisheries are being destroyed in order to produce dirt-cheap chicken feed and fish feed. The aid that flowed in after the massive tsunami of 2004 also had certain unintended consequences7. It led to the modernisation and expansion of the small-scale fisheries sector, which generated an illusory boom followed by a bust. In recent decades the governments of the nations that surround the Bay of Bengal have striven to expand and encourage their fisheries. But unfortunately these efforts have often ignored questions of long-term sustainability. Although attempts have been made to regulate fishing in the bay they have been largely ineffective. In the 1980s and 90s, fisheries expanded into new grounds and began to target new species and for a while there was an increase in catches5. But catch rates began to decline in the late 1990s and trawlers were forced to move farther and farther from their home waters. This in turn has created a little-noticed grid of conflict. In 2015 Sri Lankan authorities claimed to have spotted 40,544 Indian trawlers in Sri Lanka’s territorial waters8. Seventy trawlers were seized and 450 fishermen were arrested. At least 100 deaths have been reported9. Conversely, many Sri Lankan tuna fishermen have also been arrested in India. On the other side of the subcontinent, large numbers of Indian fishermen are frequently arrested in Pakistan: 220 of them were released in December 2016, as a goodwill gesture. In Myanmar, until a ban was enacted in 2014, the catch collected by foreign fishing boats was 100 times greater than that of local fishermen10. In the troubled Arakan region, where 43% of the population is dependent on fisheries, catches have declined so steeply that many families are mired in debt11. Conflicts over fisheries and other resources are a significant but largely unnoticed aspect of the explosive tensions of the region. The Mergui archipelago on the Thai-Myanmar border is one of the more secluded parts of the Bay. In the late 19th century an English fisheries officer described this area as being “literally alive with fish”1. Today the archipelago’s sparsely populated islands remain pristinely beautiful while some of its underwater landscapes present scenes of utter devastation. Fish stocks have been decimated by methods that include cyanide poisoning. The region was once famous for its coral reefs; these have been ravaged by dynamite-fishing and climate-change induced bleaching. Yet the exploitation of these waters continues without check. At night specially equipped, long-armed boats materialise around the islands and shine high-powered green lights into the water to attract plankton and the squid that follow in their wake. After nightfall, a glow that is bright enough to be visible from outer space12 hangs above the archipelago, like a miasmic fog. These squid boats, some of which are probably crewed by men who have been trafficked like slaves13, help to make Thailand the world’s largest exporter of squid – at least for the time being. At the same time the bay’s ecosystems are also being disrupted by other environmental pressures. Several large rivers empty into the bay, carrying vast tides of untreated sewage, plastic, industrial waste and effluent from the agriculture and aquaculture industries14. The impact of this pollution could be catastrophic. The high load of organic pollutants, coupled with the diminution of the fish that keep them in control, could lead to massive plankton blooms, further reducing the water’s oxygen content. Last month a multinational team of scientists reported an alarming finding – a very large “dead zone” has appeared in the bay. Apart from sulphur-oxidising bacteria and marine worms, few creatures can live in these oxygen-depleted waters15. This zone already spans some 60,000 sq km and appears to be growing16. The dead zone of the Bay of Bengal is now at a point where a further reduction in its oxygen content could have the effect of stripping the water of nitrogen, a key nutrient. This transition could be triggered either by accretions of pollution or by changes in the monsoons, a predicted effect of global warming. What is unfolding in the bay is a catastrophic convergence of flawed policy, economic over-exploitation, unsustainable forms of waste management, and climate change impacts that are intensifying in unpredictable ways. The scientists who identified the bay’s dead zone warn that this stretch of ocean is approaching a tipping point that will have serious consequences for the planet’s oceans and the global nitrogen cycle. Should the bay’s fisheries collapse there will also be very serious human consequences, including intensified conflict and mass displacement. If millions of people lose their livelihoods then we can be sure that the resultant churning of populations will create huge new streams of migration, across the bay, the Indian Ocean, and indeed, the planet. Recent refugee flows in the region suggest that such a process may have already begun. For these issues to be addressed there needs to be a sea change in governmental attitudes and policies. For too long the governments of the region, often with international encouragement, have looked upon the sea as a bottomless resource pit to be despoiled at will. They need instead to view it as a wilderness that requires conservation and informed management, in consultation with the communities that are dependent on it. The situation demands carefully crafted solutions since it involves millions of livelihoods that are already imperilled by the dwindling of the bay’s resources. • Amitav Ghosh is a novelist and non-fiction writer. His most recent book is The Great Derangement: Climate Change and the Unthinkable. • Aaron Savio Lobo has a PhD in marine conservation from the University of Cambridge. He is currently a technical advisor for the Indo-German Biodiversity program of the GIZ (Deutsche Gesellschaft für Internationale Zusammenarbeit ) in India. The views and opinions expressed in this article do not necessarily reflect those of his organisation. 1. Amrith, S. Crossing the Bay of Bengal: the furies of nature and the fortunes of migrants. (Harvard University Press Cambridge, MA, 2013). 2. BOBLME. Results and achievements of the BOBLME Project. (2015). 3. Swathilekshmi, P. S. & Johnson, B. Migrant labourers in the primary sector of marine fisheries: A case study in Karnataka. 38 (Central Marine Fisheries Research Institute, 2013). 4. Vivekanandan, E., Srinath, M. & Kuriakose, S. Fishing the marine food web along the Indian coast. Fish. Res.72, 241–252 (2005). 5. Bhathal, B. & Pauly, D. ‘Fishing down marine food webs’ and spatial expansion of coastal fisheries in India, 1950–2000. Fish. Res.91, 26–34 (2008). 8. Scholtens, J. Fishing for access in transboundary waters. The reproduction of fishers’ marginality in post-war northern Sri Lanka. (University of Amsterdam, 2016). 9. Suryanarayan, V. & Swaminathan, R. Fishing in Palk Bay: contested territory or common heritage? Thinking out of the box. (Ganesh and Co.). 11. Ei Cherry Aung. As catch and sales fall, Burma’s fishermen sink into debt. The Irrawaddy (2017). 12. Schonhardt, S. What’s the one thing in Thailand visible from space? The Wall Street Journal (2014). 13. Jones, S. Trafficked into slavery on a Thai fishing boat: “I thought I’d die there”. The Guardian (2015). 14. Kaly, U. L. Review of land-based sources of pollution to the coastal and marine environments in the BOBLME Region. 100 (FAO-BOBLME Programme, 2004). 15. Bristow, L. A. et al. N2 production rates limited by nitrite availability in the Bay of Bengal oxygen minimum zone. Nat. Geosci10, 24–29 (2017).

Gopinadha Pillai C.S.,Central Marine Fisheries Research Institute
Indian Journal of Animal Sciences | Year: 2010

Precise estimation of the biodiversity of corals from any area is subject to variation due to uncertainty of synonymy. Corals exhibit very high intraspecific skeletal variation depending on the physiographic and hydrographic condition. The present paper describes overview of coral resources in Indian seas, their biology and taxonomy, anthropogenic stress on coral reefs, conservation and research efforts being put by various organisations.

Food habits of the blue swimmer crab, Portunus pelagicus were investigated using specimens collected from trawl catches in the Mandapam region, Tamil Nadu, along the east coast of India (9°20-25′N 79°5-10′E), during the period January to December, 1999. The stomach contents of 452 crabs, ranging from 61 to 180 mm carapace width, were analysed. Their diet included crustaceans, molluscs, fishes, unidentifiable matter, and debris. In adult crabs, crustaceans constituted the dominant food source and these were present in 78.43% of the stomachs analysed. The stomach contents of juveniles and sub-adults were dominated by debris. There was no significant difference between sexes in the frequency of occurrence of food items or in their "percentage points" [= the (virtual) percentual contribution to the fullness of a 100% full stomach]. However, there was a difference between the stomachs of ovigerous and non-ovigerous females. There were also significant differences in the preference for food items in the different size groups of the crab. The results collected from the present study showed that P. pelagicus exhibits, in this region at least, a clear preference for crustaceans. © 2011 Koninklijke Brill NV, Leiden.

Satheeshkumar P.,Central Marine Fisheries Research Institute
Iranian Journal of Fisheries Sciences | Year: 2012

Baseline ecological studies of Pondicherry mangroves are important for monitoring, management and conservation of mangrove ecosystems. A brachyuran crab faunal assemblage at four stations of Pondicherry mangroves is described and monthly samplings were made during September 2008-August 2009. Totally 22 species of brachyuran crabs belonging to 12 genera and 5 families were recorded; crabs belonging to the family Portunidae and Ocipodidae are most dominant group represented by total of 16 species. Six species considered are as a commercially important and out of which, on three species Scylla serrata, Thalamitta crenata and Portunus sanguinolentus are catch large quantities from stations 1 and 2. Portunus pelagicus, P. sanguinolentus and T. crenata were totally absent in stations 3 and 4. Population densities of brachyuran fauna ranged from 29 -71 ind. m2, the diversity ranged from 0.96 -2.18 bit. ind -1, the richness varied from 0.42 -0.74, and the evenness varied from 0.41 -.072. Maximum diversity values were recorded during post monsoon. The crab community recorded was analyzed by univariate and multivariate statistical techniques. Crab community structure was correlated with vegetation structure, and environmental factors were positively correlated with surface water pH, salinity, tree dominance, tree diversity and tidal inundation and negatively correlated with sulphide, organic matter, senescent leaves and decaying leaves, suggesting that the mangrove vegetation is important to the crab fauna as a habitat and food supply.

Rajesh N.,Central Institute of Fisheries Education | Imelda-Joseph,Central Marine Fisheries Research Institute | Paul Raj R.,Coastal Aquaculture Authority
Waste Management | Year: 2010

Vegetable waste typically has high moisture content and high levels of protein, vitamins and minerals. Its value as an agricultural feed can be enhanced through solid-state fermentation (SSF). Two experiments were conducted to evaluate the nutritional status of the products derived by SSF of a mixture of dried vegetable waste powder and oil cake mixture (soybean flour, wheat flour, groundnut oil cake and sesame oil cake at 4:3:2:1 ratio) using fungi Aspergillus niger S14, a mangrove isolate, and A. niger NCIM 616. Fermentation was carried out for 9days at 35% moisture level and neutral pH. Significant (p<0.05) increase in crude protein and amino acids were obtained in both the trials. The crude fat and crude fibre content showed significant reduction at the end of fermentation. Nitrogen free extract (NFE) showed a gradual decrease during the fermentation process. The results of the study suggest that the fermented product obtained on days 6 and 9 in case of A. niger S14 and A. niger NCIM 616 respectively contained the highest levels of crude protein. © 2010 Elsevier Ltd.

Anju A.,Central Marine Fisheries Research Institute
Fish & shellfish immunology | Year: 2013

Because of its capacity to rapidly convert superoxide to hydrogen peroxide, superoxide dismutase (SOD) is crucial in both intracellular signalling and regulation of oxidative stress. In this paper we report the cloning of a Cu/Zn SOD (designated as pfSOD) from the pearl oyster (Pinctada fucata) using rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA of this Cu/Zn SOD contains an open reading frame (ORF) of 471 bp coding for 156 amino acids. No signal peptide was identified at the N-terminal amino acid sequence of Cu/Zn SOD indicating that this pfSOD encodes a cytoplasmic Cu/Zn SOD. This is supported by the presence of conserved amino acids required for binding copper and zinc. Semi-quantitative analysis in adult tissues showed that the pfSOD mRNA was abundantly expressed in haemocytes and gill and scarcely expressed in other tissues tested. After challenge with lipopolysaccharide (LPS), expression of pfSOD mRNA in haemocytes was increased, reaching the highest level at 8 h, then dropping to basal levels at 36 h. These results suggest that Cu/Zn SOD might be used as a bioindicator of the aquatic environmental pollution and cellular stress in pearl oyster. Copyright © 2013 Elsevier Ltd. All rights reserved.

Filtration rate and ingestion rate of different stages of Paphia malabarica larvae (D-shape, (80μm), Umbo (120μm) and veliger (180μm)) were determined in relation to feeding on various micro algae. The micro algae tested were Nannochloropsis salina, Isochrysis aff. galbana, Dicrateria inornata, Tetraselmis gracilis and Chaetoceros calcitrans at 5 or 10×103cellsmL-1. Both filtration and ingestion rate of micro algae tested were increased with increasing larval size; however, at all larval stages, C. calcitrans resulted in lower filtration and ingestion rate. Of the algal diets tested, P. malabarica larvae showed greatest filtration rate and ingestion rate with N. salina. Maximum filtration rate for N. salina was 15.7, 26.3 and 33.9μLh-1 and highest ingest rate was 15, 92 and 177cellslarva-1h-1 in D shape larvae, umbo and pediveliger, respectively. Filtration rate and ingestion rate of N. salina were always higher than those other algal species tested because of its small cell size (2μm). © 2010 Blackwell Publishing Ltd.

In this study, the interrelationships between various morphometric characters, viz., carapace width and length and chelar propodus length and height in males, as well as carapace width and length and abdominal width and length in females, were estimated using a total of 980 crabs, Portunus pelagicus. The carapace width/length - weight relationship was studied in both sexes on a total of 1188 crabs using the allometric growth equation of Von Bertalanffy. The allometric relationships between the characters of this set suggest that most relationships are positive and highly significant. The 'b' values for carapace width-weight in males and females were 3.607 and 3.293, respectively, and for carapace length-weight they were 3.049 and 2.774, respectively. The results show a significant deviation from an isometric growth pattern. An analysis of covariance indicates that there is a significant difference between sexes with respect to the carapace width-weight relationship.© Koninklijke Brill NV, Leiden, 2011.

Chakraborty K.,Central Marine Fisheries Research Institute | Lipton A.P.,Central Marine Fisheries Research Institute | Paul Raj R.,Central Marine Fisheries Research Institute | Vijayan K.K.,Central Marine Fisheries Research Institute
Food Chemistry | Year: 2010

Chromatographic purification of the dichloromethane-soluble fraction of alga, on neutral alumina, using increasing concentrations of ethylacetate/n-hexane as eluents, yielded seven labdane diterpenoids (1-7) as major constituents of green alga Ulva fasciata. Structures of these diterpenoids were established using extensive spectroscopic techniques. Antimicrobial assay showed that the compounds labda-14-ene-3α,8α-diol (2) and labda-14-ene-8α-hydroxy-3-one (4) were inhibitory to the growth of Vibrio parahaemolyticus and Vibrio alginolyticus with minimum inhibitory concentrations of 30 μg/ml by 2, and 40 μg/ml by 4, respectively against the former and 30 μg/ml by 2, and 80 μg/ml by 4, respectively, against the latter. Structure-activity relationship analyses revealed that the compounds with electronegative hydroxyl or carbonyl group(s) exhibit greater activities, apparently by proton exchange reaction with the basic aminoacyl residue at the macromolecular receptor site of virulent enzymes of pathogenic bacteria. These might provide promising therapeutic agents against infections with multi-resistant Gram-negative fish pathogenic bacteria. © 2009 Elsevier Ltd. All rights reserved.

Chakraborty K.,Central Marine Fisheries Research Institute | Paulraj R.,Central Marine Fisheries Research Institute
Food Chemistry | Year: 2010

Free-radical-scavenging activities of various solvent extracts of Ulva fasciata, a chlorophytan marine macroalga with significance as a food ingredient, from the southwestern coast of the Indian peninsula, were evaluated using in vitro tests, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) scavenging assays. Ethyl acetate (EtOAc) extract of Ulva fasciata displayed markedly stronger DPPH (89.8 ± 4.2%) and ABTS {radical dot}+ scavenging (82.6 ± 3.7%) activities at 0.1 mg/ml than dichloromethane and n-hexane extracts. Radical scavenging assay-guided chromatographic separation of the EtOAc extract, using a step gradient of petroleum ether/EtOAc yielded five major sesquiterpenoids. After 8 min of incubation the ABTS {radical dot}+ scavenging activity of one of these sesquiterpenoids was higher (71.4 ± 1.5%) than that of Trolox (44.1 ± 1.5%), and therefore may have potential as a natural antioxidant in the food industry. © 2010 Elsevier Ltd. All rights reserved.

Loading Central Marine Fisheries Research Institute collaborators
Loading Central Marine Fisheries Research Institute collaborators