New crustacean resources in the trawl fishery off Mangalore coast

Since trawling operation started during the sixties, penaeid shrimps, crabs and stomatopods formed the major part of the crustacean fishery, in trawl catches off Mangalore coast with non-penaeids and lobsters to a minor extent

Unprecedented heavy landings of juvenile Kiddy shrimp, Parapenaeopsis stylifera along Karnataka coast

Parapenaeopsis stylifera is one of the most abundant and highly valued shrimp species in India. It forms about 20% of the penaeid shrimp catch of Karnataka with the period from January to June contributing the majority of the catch. In general, the post-monsoon months of August to December is considered as a lean period for P. stylifera. During this period single day fishing trawlers land catch of a mixture of fish, prawns, stomatopods and other crustaceans. The contribution of prawns in the catch is around 10 to 20%

Photoluminescence and EPR studies of ZnS nanoparticles Co-doped with Mn and Te

ZnS nanoparticles Co-doped with Mn and Te (x = 0.05 and 0.10) have been synthesized for the first time by chemical co-precipitation method, thiophenol is used to passivate the surface of the particles. The as-prepared samples were amorphous in nature. Nanocrystallinity was induced after calcining the samples at 300oC/2hrs. The obtained nanoparticles were subjected to X-ray diffraction (XRD), Energy Dispersive Analysis of X-rays (EDAX), Transmission Electron Microscopy (TEM), hotoluminescence (PL) and Electron Paramagnetic Resonance (EPR) studies. All the samples exhibited cubic structure and the particle size was found to be 3-5 nm. EDAX revealed that the compositions did not deviate much from the target compositions. The photoluminescence studies showed emission in the red region and the emission wavelength is varied with composition. The Electron Paramagnetic Resonance (EPR) spectra showed paramagnetic nature of the samples at room temperature. EPR and PL results were quite consistent with each other. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2197

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Preparation and Characterization of NiO Thin Films by DC Reactive Magnetron Sputtering

Nickel oxide (NiO) thin films were successfully deposited on Corning 7059 glass substrates at different oxygen partial pressures in the range of 1 × 10 – 4 to 9 × 10 – 4 mbar using dc reactive magnetron sputtering technique. Structural properties of NiO films showed polycrystalline nature with cubic structure along (220) orientation. The optical transmittance and band gap values of the films increased with increasing the oxygen partial pressure from 1 × 10 – 4 to 5 × 10 – 4 mbar and decreased on further increasing the oxygen partial pressure. Using Scanning Electron Microscopy (SEM), fine grains were observed at oxygen partial pressure of 5 × 10 – 4 mbar. The film resistivity decreases from 90.48 to 13.24 Ω cm with increase in oxygen partial pressure to 5 × 10 – 4 mbar and then increased on further increasing the oxygen partial pressure. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3025

Biology and exploitation of the blue swimmer crab, Portunus pelagicus (Linnaeus, 1758), from south Karnataka coast, India

Portunus pelagicus supports indigenous as well as mechanised fishery of Karnataka coast. Trawlers accounted for 98% of the landing and the highest landing was observed during 2001-2002 (403 t). The peak fishing season for crabs was during December-June. Size range observed in the fishery was 56 to 165 mm in males and 61 to 170 mm in females. The homogeneity of sex ratio (2 test) obtained for the years 1998-2005 was 1:1. Peak spawning activity occurred during February-March. Size at maturity (50%) of females was estimated at 96 mm carapace width. Growth was isometric and males were heavier than females of similar size. By von Bertalanffy's growth plot, it was estimated that males and females reach 123 and 128 mm (CW) respectively at the end of one year and reach 156 and 160 mm respectively in two years. Longevity of P. pelagicus is estimated as 3 years in both sexes. The total mortality coefficient (Z), natural mortality coefficient (M) and fishing mortality coefficient (F) values estimated for the species were 6.3, 2.2 and 4.1 respectively. The exploitation ratio (E) was 0.65 and Lc was estimated at 87.7 mm. MSY was estimated as 367 t against the present annual average yield of 333 t. From 'Thompson and Bell yield prediction analysis it is seen that any additional 10% effort from the present level will yield only less than 10% additional catch, indicating that increasing the effort will not be economical. Restricting the catch to MSY level (367 t) is suggested as a suitable management option for the sustainability of P. pelagicus fishery from the coast

Fishery and stock assessment of Portunus sanguinolentus (Herbst) from south Karnataka coast, India

The study on the exploited fishery of Portunus sanguinolentus off south Karnataka coast during 1998- 2005, revealed that it contributed to 46% of the average annual crab landing with peak in May. The carapace width (CW) varied from 61 to170 mm in males and 56 to 160 mm in females. Percentage of females in advanced maturity stage was high during January-March. Size at maturity of females was 90 mm (CW). Carapace width-weight relationship indicated that males are heavier than females and the growth is positive isometric. The longevity of the species was estimated as 2 ½ years and males and females reach 137 mm (CW) at the end of the first year and 163 mm (CW) in two years. Females reached sexual maturity in 6 months. L∞ and K were estimated as 175 mm and 1.7 year-1 respectively. The estimated total mortality coefficient (Z) was 7.15 and fishing mortality coefficient (F) 4.18. The exploitation ratio (E) was 0.58. Size at capture (L50) was 79.2 mm. Estimated total stock was 852 t standing stock was 118 t and the MSY was 544 t. An increase in fishing effort by 10 to 20 % may enhance the catch only by 3 to 4%. It is suggested that for sustaining the fishery, the fishing effort (in hours) may be reduced by 30 to 40% from the present level of exploitation

Report on the fishery of Indian Ocean Lobsterette, (Nephropsis stewarti) along Mangalore

Ever since deep-sea trawling started, Indian Ocean Lobsterette (Nephropsis stewnrti) were landed regularly at Mangalore Fisheries Harbour. They were caught from a depth of 250- 500 m. The meat of this lobster is considered as a delicacy and is procured by processing plants for export. Since the meat content is less, the price of the lobster is Rs. 20-25 Kg

Mapping of fishery resources in trawling grounds along the Malabar-Konkan coast

Two categories of bottom trawl units are in operation along the Malabar-Konkan coast. The first category comprises of small boats (<9.75 m OAL) conducting daily trips operating trawl nets with codend mesh size of 10-20 mm and catch generally prawns, flatfishes and other finfishes