GIS based mapping of spatio-temporal distribution pattern of ribbonfish Trichiurus lepturus (Linnaeus, 1758) along Saurashtra coast, India

Abstract

Identification of spatio-temporal distribution of fish species represents fundamental information for stock assessment which in turn is essential for formulation of fishery management plans as well as for GIS based decision making. This study investigated the spatio-temporal distribution and abundance of different life stages of ribbonfish, Trichiurus lepturus (Linnaeus, 1758) off Saurashtra coast. Geographical coordinates of fishing and allied information on the time of fishing, depth of the fishing area as well as catch details were collected using a structured schedule, from selected trawlers operated from Veraval. Information was mapped using a GIS software to get the spatio-temporal distribution of the species. It was observed that juveniles were more abundant along the south Saurashtra coast whereas subadults and adults showed a discontinuous distribution with abundance in the waters off south Saurashtra as well as north Saurashtra coasts.

Unveiling the reproductive and migrative behavior of Trichiurus lepturus in a tropical environment: Insights and implications

“…However, a low number of individuals were observed during this period. This pattern has been observed for this species in various regions worldwide and is likely attributed to their migratory behavior for reproduction, which leads them toward deeper waters (James, 1960;Martins & Haimovici, 1997;Magro, 2006;Abdul Azeez et al, 2016). For instance, in the northern Gulf of Mexico, the significant occurrence of planktonic postlarvae in deep tows (at depths of 20-37 m) and their absence in surface tows, along with the absence of adult individuals in coastal areas during late fall and early winter, are considered indicative of winter spawning occurring at depths greater than 37 m (Dawson, 1967).…”

“…. Similarly, in the northeastern Arabian Sea, this species can be found at depths ranging from 10 to 200 m (AbdulAzeez et al, 2016). These studies have demonstrated correlations between depth and abundance, as well as shifts in length frequency in correspondence with different climate seasons.…”

Longtail tuna fisheries in the northern Arabian Sea off the north-west coast of India: Moving towards developing spatially explicit fisheries management strategy

“…GeoMedia Professional 2014 and its extensions were used to create georeferenced maps for the abundance and disribution of Thunnus tonggol. The data collected were entered in an MS excel 1997-2003 format compatible to GeoMedia Professional 2014 GIS platform as followed by Azeez et al (2016). Coastline and bathymetry maps were digitised from available nuatical maps and saved in shapefile format (.shp).…”

Fishery and geospatial mapping of pelagic elasmobranchs from mechanised gillnetters of Tharuvaikulam, Thoothukudi, south-east coast of India

“…In India, the application of GIS in marine fisheries has been considerably slower but much awareness has developed recently and formed one of the major topics of research during the last decade. ICAR-CMFRI also attempted and demonstrated the utility of GIS in marine fishery resource mapping (Dineshbabu et al, 2012b;Abdul-Azeez et al, 2016).…”