Studies on the Biology, Ecology and Fishery of the sea cucumber Holathuria (hetriatyla) scabra (Jaeger) from southeast coast of India

The distribution of the holothurian H. KH.) scabra indicated its availability all along coastal areas on Palk Bay from Rameswavam to Mallipattinam and along the Gulf of Hannah coast from Pamban to Ervadi and Tuticmhin,'at 4~2O m depth.The major fishing for holmthurians was done by skin diving at all the centres. The tallu valai was operated at Tuticorin and Vedalai and trawlevs were operated at Rameswaram.The fmod of H. KN.) scabra consists of ovganic matter which contains mud, sand, shell debris, bivalves and algae. Obsehvatinns indicated the species seems to be a n0n—se1ective feeder. The assimilation efficiency from sediment to faeces indicated that the faecal pellets of H. KH.) scabra are semidigested.A multiple relationship was fitted between total length, total weight, gutted weight, gonad weight and maturity stages were found significant.The fishing season for holothurians commences from October to March along Gulf of Manner coast and from March to October along Palk Bay coast.The percentage of catches recorded by skin diving, trawlere and tallu valai were 80.04%, 10.27% and 9.69% respectively. Skin diving contributes to maximum catch.The holothurians landed all along the Gulf of Manner and Palk Bay coasts constitute 25.6% and 74.4% respectively. This showed that Palk Bay coast is more productive.

Predicted impact of the sea-level rise at VellareColeroon estuarine region of Tamil Nadu coast in India: Mainstreaming adaptation as a coastal zone management option

Low-lying coastal areas are more vulnerable to the impacts of climate change as they are highly prone for inundation to SLR (Sea-Level Rise). This study presents an appraisal of the impacts of SLR on the coastal natural resources and its dependent social communities in the low-lying area of VellareColeroon estuarine region of the Tamil Nadu coast, India. Digital Elevation Model (DEM) derived from SRTM 90M (Shuttle Radar Topographic Mission) data, along with GIS (Geographic Information System) techniques are used to identify an area of inundation in the study site. The vulnerability of coastal areas in Vellar-Coleroon estuarine region of Tamil Nadu coast to inundation was calculated based on the projected SLR scenarios of 0.5 m and 1 m. The results demonstrated that about 1570 ha of the LULC (Land use and Land cover) of the study area would be permanently inundated to 0.5 m and 2407 ha for 1 m SLR and has also resulted in the loss of three major coastal natural resources like coastal agriculture, mangroves and aquaculture. It has been identified that six hamlets of the social communities who depend on these resources are at high-risk and vulnerable to 0.5 m SLR and 12 hamlets for 1 m SLR. From the study, it has been emphasized that mainstreaming adaptation options to SLR should be embedded within a coastal zone management and planning effort, which includes all coastal natural resources (ecosystem-based adaptation), and its dependent social communities (community-based adaptation) involved through capacity building

Geophysical Constraints on Structure and Tectonics of the Eastern Arabian Sea and the Adjoining West Coast of India with Special Reference to the Kerala Basin

The main objective of the present study is to model the gravity fields in terms of lithospheric structure below the western continental margin of India (WCMI) identify zones of crustal mass anomalies and attempt to infer the location of Ocean Continent transition in the Arabian Sea. In this study, the area starting from the western shield margin to the region covering the deep oceanic parts of the Arabian Sea which is bounded by Carlsberg and Cerg and Central Indian ridges in the south, eastern part of the Indus Cone in the west and falling between 630E and 800E longitudes, and 50N - 240N latitudes has been considered. The vast amount of seismic reflection and refraction data in the form of crustal velocities, basement configuration and crustal thicknesses available for the west coast as well as the eastern Arabian Sea has been utilized for this purpose

Dynamics of Infaunal Benthic Community of the Contenental Shelf of North-Eastern Arabian Sea

In this study dynamics of infaunal benthic community of the continental shelf of north-eastern Arabian sea. The benthic (under water sea) organisms play an important role in the marine food chain. It can be concluded that seasonal differences in the benthic community was observed in lower depths and absent in deeper depths. Increased richness and diversity during pre-monsoon may be related to the increased primary production which inturn influenced by the increased nutrient input due to winter convection. No single ecological factor could be considered as a master factor. In general the area supports moderately high benthic production and diversified community.

Biogeochemistry of trace metals in the Indian EEZ of the Arabian Sea and Bay of Bengal

The present study has been initiated to unravel the distribution of trace metals and its geochemical behavior in the Indian EEZ of the Arabian Sea and Bay of Bengal. Trace metal accumulation in aquatic consumers is of interest to ecologists and environmentalists so as to understand the fate and effect of contaminants in the food web dynamics and the biogeochemical cycling of trace metals. It is well established that oceanic distribution of macronutrients such as nitrate, phosphate and silicate provide critical to biological growth and related geochemical processes. In this study it can be inferred, that there is a need for a better understanding of background informations on trace metal concentrations with respect to space and time and their fluctuations in the Arabian Sea and Bay of Bengal zooplankton. Without a sound knowledge on spatio-temporal fluctuations, it will be impossible to differentiate anthropogenic metal inputs from natural background concentrations with a routine biomonitoring programme. Fe, Cu, Zn, Cd & Pb showed a slight enrichment in zooplankton from the Arabian Sea during spring intermonsoon compared to intermonsoon fall. The relative enrichment of Fe, Cu & Zn in zooplankton from the Arabian Sea during intermonsoon spring than intermonsoon fall was due to favourable bioaccumulation factors of these elements during this season. Nevertheless this study can be looked upon as a starting point for further investigations on these biogeochemically important processes, which are vital in addressing the dynamics of productivity of waters.

Marine Yeasts from the Slope Sediments of Arabian Sea and Bay of Bengal

The present study provides an account of the occurrence and diversity of marine yeasts in the slope sediments of Arabian Sea and Bay of Bengal. It also gives a clear idea about the role of yeasts in the benthic realm of marine ecosystem. The lipolytic potential of the organisms indicate the presence of rich lipid moieties in the study area. The isolates, Candida sp. SD 302 and Pichia guilliermondii SD 337 were proved to have potential oil degrading property and can be employed as bioremediators of oil spill after further characterization. The black yeasts isolated during the study area were found to have high commercial value by virtue of the by-products obtained from them. The melanin and the melanin degrading enzyme extracted from these organisms are potential bioactive materials for application in cosmetology.

Coastal Upwelling of the South Eastern Arabian Sea - An Integrated Approach

Upwelling regions occupies only a small portion of the global ocean surface. However it accounts for a large fraction of the oceanic primary production as well as fishery. Therefore understanding and quantifying the upwelling is of great importance for the marine resources management. Most of the coastal upwelling zones in the Arabian Sea are wind driven uniform systems. Mesoscale studies along the southwest coast of India have shown high spatial and temporal variability in the forcing mechanism and intensity of upwelling. There exists an equatorward component of wind stress as similar to the most upwelling zones along the eastern oceanic boundaries. Therefore an offshore component of surface Ekman transport is expected throughout the year. But several studies supported with in situ evidences have revealed that the process is purely recurring on seasonal basis. The explanation merely based on local wind forcing alone is not sufficient to support the observations. So, it is assumed that upwelling along the South Eastern Arabian Sea is an effect of basin wide wind forcing rather than local wind forcing. In the present study an integrated approach has been made to understand the process of upwelling of the South Eastern Arabian Sea. The latitudinal and seasonal variations (based on Sea Surface Temperature, wind forcing, Chlorophyll a and primary production), forcing mechanisms (local wind and remote forcing) and the factors influencing the system (Arabian Sea High Saline Water, Bay of Bengal water, runoff, coastal geomorphology) are addressed herewith.

Dynamics and Thermodynamics of the Arabian Sea Warm Pool

The present study examines the importance of low saline waters and resulting barrier layer in the dynamics of the ASWP using observational data.The oceanic general circulation models (OGCM) are very useful for exploring the processes responsible for the ASWP and their variability. The circulation and thermohaline structure stimulated by an OGCM changes a lot when the resolution is increased from mesoscale to macro scale. For a reasonable simulation of the ASWP, we must include the mesoscale turbulence in numerical models. Especially the SEAS is an eddy prominent region with a horizontal dimension of 100 to 500 km and vertical extent of hundred meters. These eddies may have an important role on the evolution of ASWP, which has not been explored so far.Most of the earlier studies in the SEAS showed that the heat buildup in the mixed layer during the pre-monsoon (March-May) is primarily driven by the surface heat flux through the ocean-atmosphere interface, while the 3-dimensional heat budget of the ML physical processes that are responsible for the formation of the ASWP are unknown. With this background the present thesis also examines the relative importance of mixed layer processes that lead to the formation of warm pool in the SEAS.

Biochemical & Pharmacological evaluation of liver oils of selected deep sea sharks and chimaeras of the Indian EEZ

With a seacoast of 8,1 18 km, an exclusive economic zone (EEZ) of 2 million square km, and with an area of about 30,000 square km under aquaculture, lndia produces close to six million tonnes of fish, over 4 per cent of the world fish production. While the marine waters upto 50m depth have been fully exploited, those beyond, remain unexplored. There is an ever increasing demand for fishery resources as food. The coastal fishery resources of the country are dwindling at a rapid pace and it becomes highly imperative that we search for alternate fishery resources for food. The option we have is to hunt for marine fishery resources. Studies pertaining to proximate composition, amino acid and fatty acid composition are essential to understand the nutraceutical values of these deep sea fishery resources. The present study was aimed to carry out proximate composition of deep sea fishery resources obtained during cruises onboard the FORV Sarise Sampada, to identify fishery resources which have appreciable lipid content and thereby analyse the bioactive potentials of marine lipids, to study the amino acid profile of these fishery resources, to understand the contents of SPA, MUFA and PUFA and to calculate the n3/n6 fatty acid contents. Though the presence of nutraceuticals was identified in the marine fishery resources their use as potential food resources deserve further investigation. So the study were carried out to calculate the hepatosomatic indices of sharks & chimaeras and conduct biochemical characterisation of liver oils of Apristurus indicus, Cenlrophorus scalprams, Centroselachus crepidater, Neoharriotta raleighana, and Harriotta pinnata obtained during cruises onboard the FORV Sugar Sampada.Therapeutic use of shark liver oil is evident from its use for centuries as a remedy to heal wounds and fight flu (Neil er al. 2006). Japanese seamen called it 'samedava' or "cure all". Shark liver oil is being promoted worldwide as a dietary supplement to boost the immune system, fight infections, to treat cancer and to lessen the side effects of conventional cancer treatment. These days more emphasis is laid on the nutritive benefits of shark liver oils especially on the omega 3 polyunsaturated fatty acids ( PUFAs) (Anandan er al. 2007) and alkylglycerols (AKGs) (Pugliese er al. I998) contained in them due to the high rise of inflammatory disorders such as arthritis, asthma and neurodegenerative diseases like Alzheimer’s, Parkinson’s and Schizophrenia. So the present study also evaluate the pharmacological properties with respect to analgesic, anti-inflammatory, anti pyretic and anti-ulcer effects of four different liver oils of sharks belonging to the Indian EEZ and to identify the components of oil responsible for these activities.The analgesic and anti-inflammatory activities of liver oils from Neoharriotra raleighana (NR), Centrosymnus crepidater (CC), Apristurus indicus (AI), and Centrophorus sculpratus (CS) sharks caught from the Arabian Sea and the Indian Ocean were compared. The main objectives also include determination of the cholesterol lowering effects of liver oils of Neoharriotra raleighana (NR) and Centrophorus sculpratus (CS) on the high fat diet induced dyslipidemia and to compare the impact of four isolipidemic diets, on levels of serum diagnostic marker enzymes, on lipid profile of blood and liver and antioxidant status of heart in male Albino rats. And also to study the efficacy of Centrophorus sculpratus (CS) liver oil against Complete Freund’s Adjuvant-induced arthritis and to compare the anti-inflammatory activity of this oil with a traditionally used anti-inflammatory substance gingerol (oleoresin extracted from ginger.). The results of the present study indicated that both (Centrophorus sculpratus liver oils as well as gingerol extracts proved to be effective natural remedies against CFA-induced arthritis in Albino rats.

Distribution, diversity and biology of deep-sea fishes in the Indian EEZ

This thesis Entitled distribution ,diversity and biology of deep-sea fishes the indian Eez.Fishing rights and responsibilities it entails in the deep-sea sector has been a vexed issue since the mid-nineties and various stakeholders have different opinion on the modalities of harnessing the marine fisheries wealth, especially from the oceanic and deeper waters. The exploitation and utilization of these esources requires technology development and upgradation in harvest and post-harvest areas; besides shore infrastructure for berthing, handling, storing and processing facilities. At present, although deep-sea fishes don’t have any ready market in our country it can be converted into value added products. Many problems have so far confronted the deep-sea fishing sector not allowing it to reach its full potential. Hence, there should be a sound deep-sea fishing policy revolving round the upgradation of the capabilities of small scale fishermen, who have the inherent skills but do not have adequate support to develop themselves and to acquire vessels having the capability to operate in farther and deeper waters. Prospects for the commercial exploitation and utilization of deep-sea fishes were analyzed using SWOL analysis.

Water characteristics and current structure of the intermediate waters in the arabian sea

At intermediate depths of the Arabian Sea, the circulation and characteristics of water are more influenced by the high saline waters from the north and low saline waters from the south of equator. The interaction of these waters which greatly differ in characteristics is less understood compared to that at the upper layers. An understanding of the nature of the intermediate waters is of vital importance not only because of the unusual characteristics of the waters but also due to the influx of the different water masses from the neighbouring Red Sea and Persian Gulf. Hence, in the present investigation, it is proposed to study the water characteristics and current structure of the intermediate waters in the Arabian Sea through the distribution of the water properties on the isanosteric surfaces of 100, 80, 60 and 4O—cl/t, vertical sections, and scatter diagrams An attempt is also made to present the potential vorticity between different steric levels to understand the circulation and mixing processes. Data collected during and subsequent to International Indian Ocean Expedition (IIOE) are used for this study. The thesis has been divided into six chapters with further sub divisions

Studies on a sea anemone ,anthopleura nicrescens(verrill) from the south west coast of India

The present study was undertaken with a view to understanding some aspects of the morphology, bionomics and physiology of the sea anemone A.nigrescens. This species was selected for the study since it is abundantly available along the coast throughout the year and can successfully reared in the laboratory without much effort. The present study deals with the following aspects of A.nigrescens. description of the species, habitat, food and feeding, digestion, studies on salinity tolerance, studies on oxygen consumption, studies on tolerance to desiccation, asexual reproduction and regeneration.