Summary of Abstract Submission

Abstract Submission No. IO50-06-0020PresentationOral

INFLUENCE OF ENVIRONMENTAL, BIOLOGICAL AND CLIMATE VARIABLES ON THE MIGRATION OF HILSA FISH IN NORTHWESTERN BAY OF BENGAL

Sourav Maity*1, T. Srinivasa Kumar1, M. Nagaraja Kumar1, Sugata Hazra2

1 ESSO-Indian National Centre for Ocean Information Services, India
2 Jadavpur University, India

ABSTRACT :

Hilsa - Tenualosa ilisha is an anadromous fish and the fish spends maximum time of life in the open ocean in Bay of Bengal (BoB). Every year with onset of summer monsoon, the species ascends towards Hugli-Matla estuary for breeding and contributes significantly in the coastal and riverine fishery of West Bengal and Odisha states in India. In this region hilsa fishing has long been targeted by the traditional gillnetters and marine trawlers from many decades. The trend of ascend in Hugli and Matla rivers seems to be declined in present years and most of the stock became restricted in coastal and near shore region hitherto which remains poorly understood. The species is overexploited and the size of the stock is highly fluctuating inter-annually. In this present study, to figure out the appearances and disappearances patterns of the fish in the coastal stretch of northwestern BoB, an effort has been provided to categorize all plausible environmental, biological and climate signals that trigger inter annual variability in quantity of ascending shoal. We observed that monsoon has significant contribution towards breeding migration and the linkages have been designated with respect to 2009 and 2010 scenario. We also observed that during monsoon the species completely stop feeding on phytoplankton, however we found lot of sand and organic debris in the gut and strong assemblage of fish in low saline region.