Trophic model of the coastal fisheries ecosystem of the southwest coast of India

The Ecopath approach and software were used to construct a trophic model of the coastal fisheries ecosystem of the southwest (SW) coast of India. The model consisted of 11 ecological groups and used estimated landings from all areas along the southwest coast (based on the sample surveys conducted by Coastal Marine Fisheries Research Institute for the years 1994, 1995 and 1996). The trophic model suggests high catch levels, particularly for the large and medium predators, demersal feeders and detritivores. The biomass estimates in the trophic model were comparable to the biomass estimates from trawl surveys based on the swept area method for the southwest coast.Fishery resources, Demersal fisheries, Fishery surveys, Biomass, Population density, Shrimp fisheries, Catch/effort, Trawling, Mathematical models, Coastal fisheries, ISW, India,

A preliminary assessment of the coastal fishery resources in India: socioeconomic and bioeconomic perspective

India is endowed with a continental shelf of 0.5 million km2 and an exclusive economic zone (EEZ) of about 2 million km2. Almost half (39%) of the Indian population utilizes the marine fisheries resources. India ranked sixth worldwide in total fish production (4.95 million t) and second in inland fish production (2.24 million t) during 1995 - 96. Fish production expanded from 0.75 million t in 1950 - 51 to 4.95 million t in 1995 - 96, giving a significant increase at a cumulative growth rate of 4.2% per annum. Marine fish production increased from 0.53 million t in 1950 - 51 to 2.71 million t in 1995 - 96. The contribution of the fisheries sector to the total gross domestic product (GDP) improved from 0.75% in 1980 - 81 to 1.28% in 1994 - 95, with marine fisheries providing employment opportunities both in the production and post-harvest sectors. Subsidiary employment in fishing includes boat building and repair, net mending, repair of engines and supply of diesel, kerosene and other essential items. Women are mostly engaged in post-harvest operations like net mending, fish processing, packing and selling of fish and fish products. The contribution to foreign exchange earnings by the fishery sector substantially increased from Rs46 crores in 1960 - 61 to Rs4 697 (US$121*) in 1997 - 98. India exports about 55 types of marine products to different countries in Southwest Asia, Europe and USA. The total quantity of marine product exports rose from 97 200 t in 1987 - 88 to 307 337 t in 1994 - 95 giving an equivalent export value of Rs53 000 lakhs to Rs357 500 lakhs**. The marine fishing sector can be classified into: (a) non-motorized artisanal sector using country craft with traditional gear; (b) motorized sector; (c) mechanized sector using inboard engines of 50 to 120 HP; and (d) deep sea fishing with bigger boats (25 m and above) and engines of 120 HP and above. In 1996, India had a total fishing fleet of 238 125 units comprising 160 000 traditional craft, 31 726 motorized craft (converted from traditional) and 46 918 mechanized vessels operating different gear combinations. For artisanal fishing, the use of canoe and boat seine in Kerala provided the highest net income of Rs0.10 lakh with an annual catch of 51 t and an initial investment of Rs0.85 lakh. In motorized fishing, canoe and ring seine in Kerala offered a net income of Rs0.98 lakh with an annual catch of 220 t and an initial investment of Rs5.0 lakh. All major fishing units in Kerala, Tamil Nadu and Gujarat have higher profits not because of higher levels of fish catch but due to a better fish price. In the motorized sector, the increase in the price of fish over the years is greater than the increase in fuel expenditure. Small trawlers, purse seiners, dol-netters, gillnetters, pair trawlers and sona boats are the major types of mechanized fishing units operating in the inshore waters (up to 50 m depth). Trawlers and gillnetters are mostly operated along the Indian coasts whereas the fishing fleet mentioned above is confined to certain regions only. A small trawler (32Æ - 36Æ) has a net income of Rs0.90 lakh with an annual catch of 72 t and initial investment of Rs5.2 lakh in Karnataka. A purse seiner has a net earning of Rs3.14 lakh per year with an annual catch of 280 t and an average investment of Rs10 lakh. However the average value of fish caught in a purse seiner is Rs4.29 per kg set against the break-even cost of Rs3.16 per kg. To assess the economic sustainability of Indian marine fisheries in the period 1985 to 1998, the surplus production model or Schaefer Model was applied. Based on this, the maximum sustainable yield (MSY) was estimated at 2 353 726 t with an estimated effort of 984 586 annual fishing hours (AFH). Using the Fox surplus production model, MSY was equal to 2 973 752 t with an effort of 6 126 232 AFH. Note that actual yield during that period was 2 441 043 t with an effort of 12 97 092 AFH. This is indicative of over-fishing in the Indian Sea and Bay of Bengal. A number of management strategies can be applied to reduce the fishing pressure on the coastal areas of India. These are: (a) a ban of certain fishing gear and restricted entry to over-exploited fishing grounds; (b) the promotion of alternative/subsidiary income and emphasizing the importance of mariculture/aquaculture; (c) effective implementation of small scale fishery development projects like infrastructure and service facilities; (d) coastal zone management including protection of marine habitats; and (e) information dissemination and education on the importance of fisheries resources.Fishery resources, Fishery surveys, Biomass, Population density, Shrimp fisheries, Catch/effort, Trawling, Mathematical models, Coastal fisheries, Marine fisheries, Ecosystems, Socioeconomic aspects, Artisanal fishing, Ecnonomic benefits, ISW, India,

Marine fisheries along the southwest coast of India

Marine fisheries production in India has increased from 0.5 million t in 1950 to 2.47 million t in 1997. The gross value of fisheries landings in India was US$2.37 billion in 1997. The contribution of fisheries to the Gross Domestic Product (GDP) has risen from 0.7% in 1980 - 81 to 1.2% in 1994 - 95. The contribution to agricultural GDP has risen from 1.9% to 4%. Fisheries production also plays a critical role in food security and livelihood in rural areas. The southwest (SW) coast, while only 16% of the Indian coastline, is an important area for marine fisheries production, contributing 31.7% (0.74 million t) in 1993 - 98. This production is dominated by pelagic (59% of landings) and demersal species (23%). However, the open access system has resulted in rapid increases in fishing effort, particularly in the coastal areas. The density of fishers inshore has increased from 3.6 to 8.5 fishers per km2 in the past four decades. This excess effort has resulted in overfishing of the stocks and lower economic rent from the fishery. The overall objective of coastal fisheries management along the southwest coast of India is sustainable coastal fisheries development. This requires key ecological, social, economic and administrative issues to be addressed. Ecological sustainability requires the reduction of the excess effort through limited entry and effort reduction schemes, appropriate exploitation patterns through improved gear selectivity and restoration of the degraded coastal environment through integrated coastal zone management initiatives. Key social interventions include: creation of alternative employment to reduce fisher numbers, prevention/management of increasing intra- and inter-sectoral conflicts and empowerment of artisanal fishers through co-management schemes, social legislation and improved support/welfare schemes. The key economic issues include declining earnings, particularly of artisanal fishers, which requires; optimizing fleet composition for economic returns, improvement of the marketing system and cold storage chains, improvement of post-harvest processes to increase product value. The key administrative needs are a strong fisheries policy that balances welfare concerns with sustainability, effective implementation of regulations, and increased government resources for fisheries management. Project briefs covering the key interventions are provided, however these require further review and improvement in collaboration with concerned stakeholders.Fishery resources, Catch/effort, Population characteristics, Coastal fisheries, Marine fisheries, Ecosystems, Economic benefits, Fishery industry, Capture fishery economics, Fish consumption, Fishery policy, Legislation, Fishery management, Flood plains, Demersal fisheries, Pelagic fisheries, Socioeconomic aspects, Surveys, Marketing, Fish storage, Fishing gear, ISW, India,

Group Norms and Consumer Behaviour

The impact of group norms on forming consumer behaviour is an important attribute of man’s social life. The market segmentation principles acknowledge the presence of this phenomenon. People belong to different age group, professional status, income levels, educational status etc. are seemed to display some specific consumer behaviour that can be attributed to a particular group. The present study attempts to find the influence of certain selected group norms on consumption pattern.Group norms, peer influence, consumer behaviour, culture and consumption, social norms

कर्कट कृषि और ग्रामीण विकास

कृपया पूरा लेख पढे

Soft Computing for Robust Secure Wireless Reception

Soft computing is a collection of different computing methodologies that include neuro computing, fuzzy logic, evolutionary computing, and probabilistic reasoning. These are aimed to exploit the tolerance for imprecision and uncertainty to achieve tractability, robustness, and low solution cost. This paper presents a brief overview of soft computing components, followed by typical realization, via simulation of a wireless receiver employing a hybrid soft computing technique to illustrate its application in a fading signal propagation scenario.Defence Science Journal, 2009, 59(5), pp.517-523, DOI:http://dx.doi.org/10.14429/dsj.59.155

Current Status of fisheries for tunas and tuna-like fishes in India

The Indian tuna fishery comprises two distinct segments, the coastal fishery and the oceanic fishery. The main components of the coastal tuna fishery are the gillnet fishery around mainland India, in which different species of tunas and tunalike species occur, and the pole-and-line and troll line fisheries exploiting skipjack and young yellowfin tuna around the Lakshadweep Islands. The oceanic fishery uses exclusively longlines, targeting large deep-swimming yellowfin and bigeye tunas. The status of the coastal fishery was last reviewed by Pillai et al. (1995), and that of the oceanic fishery by Somvanshi and John (1995). The present paper gives an update of the national tuna fishery, both the coastal and oceanic segments, and its recent trends. All three groups of resources (tunas, billfishes and seerfishes) are covered

Length-weight relationship and certain biological aspects of the Indian white shrimp Fenneropenaeus indicus (H. Milne Edwards, 1837) exploited by trawls in the Arabian Sea off Kerala coast, India

Length-weight relationship (LWR), sex ratio and maturity of Fenneropenaeus indicus (H. Milne Edwards, 1837), was analysed based on samplings from coastal trawl fishing grounds in the Arabian Sea off Kerala coast, India. The male to female ratio (1:1.27) did not vary significantly from the hypothetical 1:1 ratio. Length at maturity (Lm50) was estimated at 122 mm total length for females. The LWR did not differ significantly between male and female shrimps. The information generated from this study will enhance knowledge on the biology of the species and assist in assessment and management of its stock

चेन्नई और नीण्डकरा बन्दरगाह में अवतरित ब्राकिचूरन कर्कटों की जैवविविधता – एक झलक

कृपया पूरा लेखा पढ

Incidential catch of sea turtles in India

Sea turtles are found all along the coast of India including the Lakshadweep and Andaman & Nicobar Islands. Five species inhabit the Indian waters. All the species are capable of taking long distance migration