Spatial structure and distribution of ribbonfish Trichiurus lepturus Linnaeus, 1758 along the eastern Arabian Sea

spatial structure and distribution of ribbonfish in eastern Arabian Sea

Abstract

Ribbonfish Trichiurus lepturus is one of the most important pelagic fish resources in India.
The west coast of India (WCI) is considered to be the major region where the species is
abundant and forms a sizeable fishery. Determining the spatio-temporal abundance of fish
is a key requirement for sustainable resource harvest. This paper illustrates the spatial
structure and distribution of ribbonfish along the WCI using the geostatistical technique,
semi-variogram modelling. The spatio-temporal distribution map was generated by kriging
interpolation using the global neighbourhood in the study area. The results show that the
areas of higher abundance of ribbonfish shifted between seasons, abundance along the
northern region was high during the post-monsoon, while later shifting southward up to
17°N, peaking between 18°N and 19°N. Furthermore, summertime peak abundance tended
to be more coastal in the Mumbai region. Ribbonfish abundance was relatively lower along
the southern region i.e., below 15°N year-round. This finding provides additional information
to fishery managers and policymakers which will help improve the sustainability of fisheries
coupled with traditional fisheries management measures

Keywords:
Arabian Sea, GIS, Geo-statistics, Species distribution
modelling, Spatiotemporal management