Ecosystem structure and trophic dynamics of an exp

Authors: Sachinandan Dutta Kunal Chakraborty Sugata Hazra

Publish Date: 2017/01/07

Volume: 83, Issue: 2, Pages: 145-159

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Abstract

A trophic structure model for commercial fisheries of Sundarban Estuary in the northern Bay of Bengal BoB is developed using the mass balance modeling software Ecopath Version 64109920 In this model we simulated 15 functional groups spread across an area of 17049 km2 The mean trophic level of the present study area is 2716 The ecotrophic efficiency of the present studied ecosystem is in the range of 0424 of medium demersals and 0961 of medium pelagics Penaeid prawn small pelagics and medium pelagics are the most exploited groups of this ecosystem The coastal northern BoB food web is mainly detritivorous and planktivorous phytoplankton and detritus positively affected almost all the functional groups and top predators are essentially absent in the system The zooplankton and benthos have negative impacts on themselves because of cannibalistic behavior The average catch per net primary production ie the gross efficiency of the system is around 0001 The system is low trophic and efficient Proper ecosystembased management practice can improve the efficiency of this overexploited ecosystemThe authors are grateful to the fishermen from the West Bengal coast for their help in data collection The authors also humbly acknowledge the Indian National Centre for Ocean Information Services INCOIS for funding the Potential Fishing Zone PFZ validation project for conducting the present study The second author also gratefully acknowledges Director INCOIS for his encouragement and unconditional help This is INCOIS contribution number 270 The authors also humbly acknowledge Isaac Kaplan and Chris Harvey of NOAA Fisheries Northwest Fisheries Science Center for their valuable comments and suggestions The authors are thankful to Abhra Chanda for correction

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