Role of rainfall in the breeding of Labeo rohita (Ham.), Cirrhinus mrigala (Ham.), Catla catla (Ham.), at Damdama (Haryana), a semi-arid zone

The role of several environmental factors on the breeding and hatching of fish has been studied by many earlier investigators. Perfection in the hypophysation technique has helped to some extent in by-passing the environmental variables such as temperature, light and rain. With the use of a modern fish hatchery, it is possible to attain maximum success in breeding and hatching, even without rains; reference is given to studies carried out regarding the role of rainfall in the breeding of Labeo rohita, Cirrhinus mrigala, Catla catla.

Breeding of Indian major carps and common carp in semi-arid zone of Haryana under controlled environment

Vast barren lands are lying vacant in the semi-arid zone of India, which can effectively be utilised for fish farming. Experiments conducted in semi-arid conditions at Damdama indicated that it is possible to breed Indian major carps and common carp under controlled conditions of modern carps hatchery CIFE D-80 without depending on rain.

Performance of paddy-cum-prawn culture in rainfed low land ecosystem of Sunderbans

Performance of both paddy (Var. NC 492) and prawn Penaeus monodon were assessed for two years during wet-season in rainfed lowland ecosystem with a view to study the economic viability of paddy-cum-prawn culture in the coastal saline zone of West Bengal. Both mono and dual culture of paddy and prawn were tried in the study. Fingerlings of prawn (α 35,000 haˉ¹) of 10-15 mm size were reared for about three and half months with and without fish feed. It was observed that addition of fish feed resulted in higher (57.7%) production of prawn (2.65 mg/haˉ¹) but not rice. Such increase in prawn production was 1.6 times higher when no feed was provided and 1.4 times higher when grown as sole crop. However, paddy, whether grown as mono or mixed culture, did not differ in yield significantly. In dual culture, the benefit - cost ratio was higher (6.83) when prawn was grown with feed and it was maximum (36.0) when grown without feed as sole crop. The study, therefore, indicates that paddy-cum-prawn culture under low land ecosystem of the coastal saline zone is enterprising particularly for small and marginal farmers who fear to take risk of growing prawn alone at the cost of paddy.

Macrobenthos of intertidal zone of Versova along the coast of Mumbai

To assess the biodiversity of macro benthos in the changing environment along the coast of Mumbai, the intertidal zone of Versova was identified. The water quality in this intertidal region was poor with low pH, salinity and dissolved oxygen, and high nitrite, nitrate, phosphate and ammonia. The substratum was sandy with 1.29% organic matter in it. Mean faunal density of 2257 no./m² was recorded during the study which was mainly contributed by polychaetes (83.5%) followed by amphipods (14.5%), while other groups represented were isopods, crabs, hermit crabs, unidentified decapods, pelecypods and gastropods. Average biomass of 34.83 g/m² (93.7%) was contributed by polychaetes. Shannon and Wiener Index (0.4107) indicated heavy pollution in the intertidal area of Versova.

A Preliminary survey of 21 Ceylon lakes. 3. Parasites and predators, food of fish, and marginal fauna

Three nematodes, two acanthocephalans and three cestodes were collected by dissecting 15 species of fish. Of these parasites only Hedruris sp. a larval nematode is responsible directly for the death of fish, since it is found in predatory species a reduction of these might prove of considerable consequence to fish, production. Bothriocephalus gowleonensis, a cestode probably introduced from China with Chinese carp, was recorded in an indigenous carp Puntius sarana. This parasite causes heavy mortality in grass carp in China and is a potential danger to local species. A single crustacean parasite was recorded. It is likely that they are widespread. No protozoa were recorded but there can be little doubt that they occur in local freshwater species and may be of considerable importance in fisheries. Several predators (insects, fish and other vertebrates) were recorded and are doubtless of considerable importance. However, the role of parasites and of predators (especially fishes) in relation to the productivity of fisheries can hardly be assessed at present and needs further study. A study of the fauna found at the shallow edges of 21 irrigation reservoirs showed an abundance of fauna in the low-country reservoirs whilst the up-country reservoirs had a poor fauna. The fauna showed insects, crustacea and mollusca in this order of abundance. The presence of insect and molluscs feeding fish in our fauna shows that these rich sources of food are being utilised.

Alternative uses of partitioning interwell tracer tests for DNAPL source zone characterisation

The heterogeneous nature of the subsurface and associated DNAPL morphologies often poses the greatest limitation to source zone clean-up strategies. Hence, detailed site characterisation techniques are required. The data presented in this paper has been collected from a series of laboratory 2-D tank experiments and numerical simulations of Partitioning Interwell Tracer Tests (PITT) in a wide range of aquifer conditions and DNAPL morphologies. Alternative uses of tracer breakthrough data have been developed In order to characterise the mass flux generated from the DNAPL source. By combining the laboratory and numerical data, a relationship between normalised mass flux and tracer-based average source zone DNAPL saturation has been established. Knowledge of such a relationship allows remediation targets to be identified, clean-up efficiencies to be evaluated, and increases the accuracy of any risk assessment.

200 mile Exclusive Economic Zone and fishery development in Sri Lanka

Following details of the marine fishery resources of Sri Lanka, prospects for fishery development with respect to the 200-mile Economic Zone are examined, outlining also the 5-year fisheries development plan (1979-83).

Consumption pattern and consumer preference for value-added fish and fish products in north zone of India

Present paper attempts to analyze consumption pattern and consumer preferences towards value-added fish and fish products in north zone of India. Results reveal that socio economic variables affect consumption of value-added fish and fish products. A total of 49 percent respondents were of middle age group (35 to 50 years). All were literates except 7% from the rural area. All were purchasing fish at least once in 15 days. A total of 90% respondents in rural, 11% in semi urban and 50% in urban area were unaware of value-added fish and fish products. About 10% of respondents had consumed it, out of which most were from urban area. Demand analysis by Cobb Douglas (CD) Demand function revealed that when price of fish, price of the substitutes, income of family and family size were used as independent variables, variation in demand of fish explained by CD Demand function was about 39% in urban area, 24% in semi urban area and 22% in rural area. From Garette ranking technique major problems in fish consumption found were irregular supply, lack of fresh fish, high price and presence of bones in fish. While lack of awareness, unavailability, no preference and unacceptable taste were major problems for consumption of value-added fish and fish products.

Report of the training course on seagrass conservation and monitoring in Myanmar Coastal Zone, Mawlamyine University, Myanmar, 26 April-3 May, 2013

A training course on seagrass conservation and monitoring was conducted at Mawlamyine University and Ngapali Beach government department and Non-Government Organizations (NGO) trainees.

Chemical ecology fatty acids of mollusks dominant species in intertidal zone of Chabahar Bay

Chemical ecology is the science of study and analysis of natural chemical products in result of biochemical processes in organisms and their reactions to variations of ecological and environmental parameters. In marine chemical ecology the existence of natural products in aquatic organisms and their ecological roles in marine animals and their reactions to environmental parameters variations will be studied. Among them, fatty acids are the most various and abundant ones in natural products which had been extracted from many marine organisms such as mollusks and algae. In this study selected animals were the dominant species of mollusks in intertidal zone of chabahar bay including gastropods, bivalves and polyplacophora classes. Nerita textilis and Turbo coronatus species are among gastropoda, Saccostrea cucullata is from bivalve, and Chiton lamyi is from polyplacophora. After seasonal sampling, separation and identification of natural products of these species, fatty acids had been isolated and identified by GC mass chromatography and their seasonal variations had been identified. In addition environmental factors of the location including pH, salinity temperature, dissolved oxygen, chlorophyll a and nutrients were measured monthly. Then the effect of seasonal variations of environmental factors on fatty acids had been studied by applying statistical analysis. GC/MS resulted thirteen fatty acids, which the most importants were myristic, stearic, oleic, palmitoleic, arachidonic and eicosapentaenoic acids. In majority of species palmitic acid was most abundant than the others and saturatedes had the most percentage levels than unsaturated ones. Although seasonal variations of identified fatty acids was not similar in species, but the majority of unsaturated ones had their maximum during winter, while saturated acids reached their maximum in summer. Statistical Analysis showed the strong correlations between Environmental factors and some fatty acids and temperature, nitrate, silicate and pH had strong correlations in all species. The species was studied from the point of lipid content and the results showed a good quality of lipid content in the selected species in the intertidal zone of Chabahar bay.