42 resultados para ecology, semi-demersal fishes, fisheries
Resumo:
Cochin backwaters, a tropical barbuilt estuary is well known for its prawn, molluscan and demersal fisheries. Also it formed the dumping area for sewage,235 retting of husks and discharge of effluents from industries located on either side of it. As a result the fishery is being gradually dwindled year after year due to the lowering of the water quality. The effect of industrial polution on the benthic community of this tropical estuary was worked out. An area extending over 21 km from the mouth of the estuary to upstream of industrial belt was selected. Temporal and spatial variations of 16 environmental parameters at 9 stations along the area were monitored monthly during 1981. Benthic fauna of these 9 stations consisted of amphipods , polychaetes, isopods, tanaidaceans, molluscs and other crustaceans (Decapods, Acetes, Alpheids, Balanus, insect larvae, chironomid larvae, cumacea and some fresh water forms ). Apart from these, sea anemone, flat worms, nematodes, sipunculoids, echinoderms and fishes were also encountered. 75 species belonging to 31 faunal groups were identified. Of these 31 groups, amphipods, polychaedes, isopods, tanaidaceans and molluscs were numerically abundant. Rest of the 26 groups (including 13 riverine forms) were found less significant due to their rare occurrence/low numerical abundance. Polychaetes and molluscs were the only major groups present at all the stations.
Resumo:
Detailed information on the biology of fishes is an essential prerequisite for their proper conservation, management and exploitation. An amplified knowledge on the biology isfundamentally essential to plan sound management policies for rational utilization of Nemipterid fishes along the Indian coast. Any information on the biochemical composition of fishes will be of immense use in assessing their nutritive value. The importance of understanding body composition during growth is essential in production studies. Detailed work on Nemipterid fishes has been done in other parts of the world whereas along the Indian coast_ not much work has been carried out. Hence the present investigation is undertaken on the systematics of Nemipterids available at Cochin and the biology and biochemical aspects of_N. jagonicus and_M. mesogrion
Resumo:
Reducing fishing pressure in coastal waters is the need of the day in the Indian marine fisheries sector of the country which is fast changing from a mere vocational activity to a capital intensive industry. It requires continuous monitoring of the resource exploitation through a scientifically acceptable methodology, data on production of each species stock, the number and characteristics of the fishing gears of the fleet, various biological characteristics of each stock, the impact of fishing on the environment and the role of fishery—independent on availability and abundance. Besides this, there are issues relating to capabilities in stock assessment, taxonomy research, biodiversity, conservation and fisheries management. Generation of reliable data base over a fixed time frame, their analysis and interpretation are necessary before drawing conclusions on the stock size, maximum sustainable yield, maximum economic yield and to further implement various fishing regulatory measures. India being a signatory to several treaties and conventions, is obliged to carry out assessments of the exploited stocks and manage them at sustainable levels. Besides, the nation is bound by its obligation of protein food security to people and livelihood security to those engaged in marine fishing related activities. Also, there are regional variabilities in fishing technology and fishery resources. All these make it mandatory for India to continue and strengthen its marine capture fisheries research in general and deep sea fisheries in particular. Against this background, an attempt is made to strengthen the deep sea fish biodiversity and also to generate data on the distribution, abundance, catch per unit effort of fishery resources available beyond 200 m in the EEZ of southwest coast ofIndia and also unravel some of the aspects of life history traits of potentially important non conventional fish species inhabiting in the depth beyond 200 m. This study was carried out as part of the Project on Stock Assessment and Biology of Deep Sea Fishes of Indian EEZ (MoES, Govt. of India).
Resumo:
The vast areas of derelict swamps covered by macrophyton and swarmed by insects scattered in different parts of India are at present either under total negligence or utilized as waste disposal dumps. Eventhough Indian subcontinent is ranked among the first ten fish producing countries in the world, the fish production is not at par with the increasing need of protein in the average Indian diet. So the water areas which become unusable for conventional human activities like the swamps could be used for fish culture which would increase the availability of protein in the form of fish flesh, thus providing new opportunities to the fishermen. But the conversion of swamps for fish culture would entail considerable expenditure. Hence the significance of a group of fresh water fishes which have made their favourable abode the muddy swamps of tropics depending partly on accessory _respiration to survive in the inimical environment. The homeostasis achieved in such a hostile, hypoxic medium make them excellent choices for culture in the derelict freshwater bodies of India. These air breathing fishes form an economically important group which are highly esteemed as food fishes in many parts of South Asia and Africa. Though their natural habitat seems to be the marshes, they have also conquered other freshwater bodies like ponds, tanks, rivers and flooded paddy fields. They can also tolerate slightly brackish waters. They are known for their nutritive, invigorating and therapeutic qualities and are recommended by physicians as diet during convalescence (Jhingran, 1982)
Resumo:
Extensive investigations on the distribution and biology of skipjack tuna are available but less is known of the bait fishes on which this fishery depends and what is known is inadequate, fragmentary and of cursory nature. The information available on tuna livebait fishes of Lakshadweep are mainly cofined to short term surverys aimed at estimating theiravailability and abundance. Reports on the biology of a few species from Minicoy are also present in the literature. This study was, therefore, prompted by a paucity of information on 1) the livebits of Minicoy, 2) livebait fishery of the northern islands and 3) knowledge of livebait ecology
Resumo:
Preliminary investigations revealed that 3. hamrur is the predominant species along the east and west coasts of India while other species are sparsely distributed and occur sporadically. In the present investigation, aspects such as population parameters, breeding and feeding biology, fishery etc. of _l:. hamrur of the north east coast of India (Fig.1) are dealt with. Studies on the distribution, abundance and stock size of priacanthids all along the Indian waters were undertaken. Taxonomic studies of the priacanthid species encountered during the study from the Indian waters is also attempted
Resumo:
Nowadays there is a growing environmental concern and the business communities have slowly started recognising environmental protection and sustainable utilization of natural resources into their marketing strategies. This paper discusses the various Ecolabeling and Certification Systems developed world over to regulate and introduce Fair Trade in Ornamental Fish Industry. Ecolabeling and green certification are considered as part of these strategies implemented partly out of compulsion from the National and International Regulatory Bodies and Environmental Movements. All the major markets of ornamental fishes like European Union, USA and Japan have started putting restrictions on the trade to impose ecolabeling as a non tariff barrier like the one imposed on seafood and aqua cultured products. A review was done on the available Ecolabeling and Green Certification Schemes available at local, national and international levels for fisheries including aquaculture and ornamental fish trade and to examine the success and constraints faced by these schemes during its implementation. The primary downside of certification is the multiplicity of ecolabels and cost incurred by applicants for certification, costs which may in turn be passed on to consumers. The studies reveal serious inadequacies in a number of ecolabels and cast doubt on their overall contribution to effective fisheries management and sustainability. The paper also discusses the inititive taken in India to develop guidelines for Green Certification of Fresh water ornamental fishes.
Resumo:
Habitat ecology and food and feeding of the herring bow crab, Varuna litterata of Cochin Backwaters, Kerala, India were investigated for a period of one year (April 2011-March 2012). Among the 15 stations surveyed, the crabs were found to occur only in 4 stations, which had a close proximity to the sea. Sediment analysis of the stations revealed that the substratum of these stations is sandy in nature and is rich in organic carbon content (0.79% to 1.07%). These estuarine crabs is euryhaline and are found to be distributed in areas with a sandy substratum, higher organic carbon content and more tidal influx. The stomach contents analysis of crabs examined showed that their diet included crustacean remains, plants, sand and debris, fishes, miscellaneous group and unidentified matter. In adults and sub-adults, crustaceans formed the dominant food group, while in juveniles, sand and debris formed the dominant group. From the present study, V. litterata was found to be a predatory omnivore capable of ingesting both animal and plant tissues
Resumo:
The Indian ornamental fish industry is divided into two-the domestic market and the export market. 90% of the freshwater ornamental fish exported from India are wild caught indigenous species. The study formed the criteria and indicators assessing the sustainability of wild caught ornamental fish exported from India. These indicators were then analyzed for their interactions, connections, linkages and relationships using cognitive mapping. The work is first of its kind in the ornamental fisheries
Resumo:
Globally most of the conventional fish stocks have reached a state of optimum exploitation or even over-exploitation; efficient utilization of non-conventional resources is necessary to meet the supply-demand gap for protein supply. Mesopelagic fishes can be considered as one such promising resource for the future, if appropriate harvest and post-harvest technologies are developed. Increasing human population and increasing demand for cheaper food fishes has made myctophids a possible potential resource for future exploitation and utilization. Earlier studies indicated the abundance of Diaphus spp. in the eastern and northeastern Arabian Sea. The present study also indicates the dominance of Diaphus spp. in the deep sea trawling grounds of south west coast of India. Commercial viability of the myctophid fishing in the Indian waters has to be worked out. The present catch estimation is based on the Stratified Random Sampling Method from the landing data. As the coverage of sampling area was limited and the gear efficiency was not standardized, the data generated are not precise. A counter check for the estimates is also not possible due to the absence of comparable works in the study area. Fish biomass estimation by acoustics survey coupled with direct fishing would only confirm the accuracy of estimates. Exploratory surveys for new fishing areas to be continued, for gathering the distribution, abundance, biological and ecological data and map the potential fishing ground on a GIS platform and the data should be provided to the commercial entrepreneurs. Generally non-conventional and non-targeted resources are under low fishing pressure and exploitation rates. Low values of fishing mortality and exploitation rates indicate that removal from the stock by fishing was only nominal from the present fishing grounds. The results indicate that the stock is almost at virgin state and remains grossly underexploited. Since the extent of distribution and abundance of the stock in the ecosystem remains to be ascertained, sustainable yield could not be estimated. Also the impact of myctophids harvest, on other commercially important fishes, has to be studied.
Resumo:
Available information on abundance of myctophids and their utilisation indicate that there is excellent scope for development of myctophid fisheries in Indian Ocean. Most of the conventional fish stocks have reached a state of full exploitation or over-exploitation. Hence there is need to locate new and conventional fishery resources in order to fill in the supply-demand gap, in the face of increasing demand for fish. Information on length-weight relationship, age and growth, spawning season, fecundity and age at maturity and information on bycatch discards are required for sustainable utilization of myctophid resource in the Indian Ocean
Resumo:
Fish and fishery products are having a unique place in global food market due to its unique taste and flavour; moreover, the presence of easily digestible proteins, lipids, vitamins and minerals make it a highly demanded food commodity.Fishery products constitute a major portion of international trade, which is a valuable source of foreign exchange to many developing countries.Several new technologies are emerging to produce various value added products from food; “extrusion technology” is one among them. Food extruder is a better choice for producing a wide variety of high value products at low volume because of its versatility. Extruded products are shelf-stable at ambient temperature. Extrusion cooking is used in the manufacture of food products such as ready-to-eat breakfast cereals, expanded snacks, pasta, fat-bread, soup and drink bases. The raw materialin the form of powder at ambient temperature is fed into extruder at a known feeding rate. The material first gets compacted and then softens and gelatinizes and/or melts to form a plasticized material, which flows downstream into extruder channel and the final quality of the end products depends on the characteristics of starch in the cereals and protein ingredient as affected by extrusion process. The advantages of extrusion process are the process is thermodynamically most efficient, high temperature short time enables destruction of bacteria and anti-nutritional factors, one step cooking process thereby minimizing wastage and destruction of fat hydrolyzing enzymes during extrusion process and enzymes associated with rancidity.