Population dynamics and stock assessment of Delegoa threadfin bream, Nemipterus bipunctatus (Nemipteridae), from the Wadge Bank, South India
Journal Title: Journal of Applied and Natural Science - Year 2018, Vol 10, Issue 1
Abstract
Fishery, population characteristics and stock estimates of Nemipterus bipunctatus were studied during June 2015 to May 2016 from Wadge Bank, South India. This region is characterised by rich biodiversity and has a conducive influence of the Indian Ocean and Arabian Sea. The asymptotic length (L∞), growth coefficient (K) and arbitrary origin of growth (t0) were estimated as 30.5 cm, 0.85/year and 0.18 respectively. The mortality parameters, total mortality rate (Z), fishing mortality rate and natural mortality rate (M) were estimated as 2.20, 0.95 and 1.25 respectively. Exploitation ratio (E) was found to be 0.57 which showed marginal over exploitation of the species at Wadge Bank. This species has two recruitment seasons, one major season from October to December and another minor season in August. The length structured Virtual population analysis revealed heavy fishing pressure on the length group 24 to 28 cm and hence the delegoa threadfin bream was not found to suffer due to recruitment overfishing in Wadge Bank. Estimated total stock, Maximum Sustainable Yield (MSY) and annual catch were 5625.9348 tonnes, 1935.321t, 2419.152t respectively. Present level of Exploitation rate (U) and Exploitation ratio (F/Z) were estimated to be 0.43 and 0.57 respectively. The study infers the cod end mesh size of the trawls operated at Wadge Bank coast has to be increase from 10 to 25 mm to increase the yield per recruit, the effort could also be maintained as the exploitation ratio of 0.50 to have maximum yield per recruit. The study suggests reducing the present level of effort by 8 percent may be needed to sustain the stock of N. bipunctatus in Wadge Bank, South India
Authors and Affiliations
K. Karuppasamy, S. David Kingston, P. Jwahar, S. Aanand, V. K. Venkataramani, V. Vidhya
Keywords
Related Articles
- EP ID EP286983
- DOI 10.31018/jans.v10i1.1579
- Views 104
- Downloads 0
Various aspects of soil and tree layer vegetation analysis in tropical dry deciduous forest of Hastinapur
Different parameters of Soil and vegetation analysis were carried out in Tropical dry deciduous forest of Hastinapur region of Uttar Pradesh. Vegetation of present study sites showed effects of various anthropogenic dist...
Correlation and path coefficient analysis for yield and its attributing traits in bread wheat (Triticum aestivum L. em Thell)
Grain yield is a complex quantitative trait and influenced by a number of attributes. To obtain higher yield information regarding association of these attributes with yield can serve as a basis in a breeding programme....
Comparative analysis of life tables of Bactrocera tau (Diptera: Tephritidae) collected from different geographical regions of North India
The tomato fruitfly, Bactrocera tau (Walker) (Diptera: Tephritidae) is one of the most important pests of the family Cucurbitaceae. Toinvestigate local adaptation, we measured the variations in life-histories and life-ta...
Effect of rain simulation on Xanthomonas oryzae pv. oryzae population density in guttation fluid and on the spread of bacterial blight in rice
Bacterial blight of rice caused by Xanthomonas oryzae pv. oryzae is most serious biotic constraint of rice production in Punjab, influenced mainly by environmental factors and nutritional factors applied to the rice crop...
Ultramorphology of antennal sensilla of open-nesting honey bees Apis florea F. and Apis dorsata F. (Hymenoptera: Apidae)
Antenna of honey bees is geniculate and has been known to possess a wide variety of sensilla. The sensilla are sensitive to odor, temperature, humidity, air pressure and gustatory stimuli. In the present investigation, u...