Turkish Journal of Fisheries and Aquatic Sciences
2011, Vol 11, Num, 2 (Pages: 291-302)
Biodiversity of Deep Sea Prawns in the Upper Continental Slope of Arabian Sea, off Kerala (South West India): A Comparison Between Depths and Years
S. R. Radhika Rajasree 1
1 Sathyabama University, Centre for Ocean Research, NIOT-SU Collaborative Research Centre, Chennai, 600119, Tamilnadu, India
DOI :
10.4194/trjfas.2011.0214
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Univariate diversity indices and multivariate cluster analysis were performed in order to evaluate the year wise and
depth wise bio diversity of deep sea prawns between 150-650 m in the upper continental slope of Arabian Sea, off Kerala,
South India. Data were collected from both exploratory surveys as well as commercial deep sea -to fishery off Kerala coast
between latitudes 7°N to 13°N. Biodiversity and species assemblage are discussed considering the different environmental
characters as well as deep sea fishing intensity. Analysis of biodiversity indices of deep sea prawns off Kerala during different
months of 2000-01 and 2001-02 revealed that the biodiversity indices were high at 150-250 and 251-350 m whereas in higher
depth zones of 351-450, 451-550 and 551-650 m, the diversity is gradually declining. The species richness was also found
maximum at relatively lower depth zones of 251-350 m in contrast to the low values registered in higher depths. The results
showed the variation in species diversity, abundance and evenness of deep sea prawns observed at various depth zones might
be due to the combined effect of both nature of substratum and the prevailing water temperature, besides the impacts of deep
sea trawling operations.
Keywords :
Deep sea prawns, bio diversity indices, species richness