నైరూప్య

Fish Diversity and Distribution in Carbyns Cove Mangrove Habitat along the South Andaman Coast in Relation to Environmental Variables

Aluri Swapna¹*, Santhosh Ram B¹ and Venu Sasidharan²

The present study investigated the fish diversity and distribution in relation to environmental variables along the South Andaman coast from October 2012 to September 2014. Bimonthly sampling was carried out using cast net and six environmental variables via air temperature, water temperature, salinity, pH, Dissolved oxygen and Biological oxygen demand were measured. A total of 136 fish species belonging to 76 genera and 43 families were encountered during the study. Sardinella melanura, Sardinella fimbriata, Sardinella gibbosa, Liza macrolepis, Valamugil seheli, Stolephorus commerosnii, Gerres abbreviates, Carangoides malabaricus and Oreochromis mossambica were the most abundant species in the creek. Principal Component analysis, non-Metric Multi-dimensional scaling and cluster analysis revealed grouping of months into three seasons (Season –I, II and –III). Seasonal variation of environmental variables was observed, with high Air temperature, water temperature, salinity and Biological oxygen demand from February to April (S- III), whereas high Dissolved oxygen and pH from May to September (S- I). Fish species richness (16.57) and diversity (4.49) were recorded higher during 2012-13 and evenness (0.99) during 2013-14. In general high fish species diversity was recorded during wet season and low during dry season. RELATE (R=0.45) and BIOENV (R= 0.59) analysis revealed environmental variable significantly (P=0.1%) influencing fish assemblage of the creek. Water temperature and salinity were best influencing the fish assemblage of Carbyn’s Cove creek. The study depicted Carbyn’s Cove mangrove habitat was endowed with diverse fishery which were significantly influenced by environmental variables. Thus it is recommended the habitat to be utilized with proper planning for better conservation and sustainable fishery.