Fishery and Exploitation of Malabar Grouper, Epinephelus malabaricus (Bloch & Schneider 1801) from Andaman Islands

Abstract

The fishery and population dynamics of groupers from Andaman Islands were studied from Jan 2010 to Dec 2011 with a special emphasis on Malabar grouper, Epinephelus malabaricus (Bloch & Schneider 1801). The average annual catch of Malabar grouper was 1,296 tonnes contributing to 21.6% of annual grouper landings. Length-weight relationship of Malabar grouper showed that growth was allometric (b=2.96) and relative condition factor (Kn) was 1 and the growth parameters viz., L∞, K and t0 were 124.60 cm, 0.80 and -0.05 respectively. The recruitment pattern was unimodal with one major peak during April to July throughout the study period. The natural mortality (M), fishing mortality (F) and total mortality (Z) were 1.05, 1.48 and 2.53 respectively and exploitation rate (E) was 0.58. The M/K ratio (1.31) was found to be well within the normal range of 1to 2.5. Catch per unit effort varied from 4 to16.5 kg.h-1. The maximum sustainable yield (MSY) was 1,107 tonnes which was lower than the average annual catch (1,296 tonnes), indicating over exploitation. The current study calls for further research in identifying the grouper fishing and spawning aggregation grounds and introduce measures for reducing fishing efforts with input and output controls to sustain the Malabar grouper fishery in Andaman waters.