Turkish Journal of Fisheries and Aquatic Sciences
2020, Vol 20, Num, 4 (Pages: 267-278)
Fishery and GIS Based Spatio-Temporal Distribution Analysis of Smooth Blaasop, Lagocephalus inermis, in South-Eastern Arabian Sea
Purbali Saha 1 ,Sujitha Thomas 1 ,T. Shailaja Salian 1 ,Dineshbabu A.P 1 ,Prathibha Rohit 1 ,Nataraja G.D. 1
1 ICAR- Central Marine Fisheries Research Institute, Mangalore Research Centre, Hoige Bazaar, Mangalore, Karnataka, India- 575 001
DOI :
10.4194/1303-2712-v20_4_03
Viewed :
2876
-
Downloaded :
2333
Investigations on distribution of species on a spatio-temporal scale has ecological and
management significance. Study was carried out in one of the productive zones of
south eastern Arabian sea on Lagocephalus inermis one of the emerging fishery
resource from 2015 to 2017 in comparison with 2008. GIS tools was used to support
fishery analysis, abundance and distribution of species. Average catch for 2015-17
period was 3456 t which showed twelve fold increase compared to 2008. Spatial and
temporal analysis of the abundance of species showed a range from 7-277 kg/hr (Catch
Per Hour) at a depth range of 20-100 m. Juveniles were observed more towards near
shore area with aggregation in clayey region. Spatial indicators (spatial dispersion,
directional dispersion and directional trend) were calculated by year. Spatial
distribution value was highest in 2016 indicating a wider distribution of L. inermis,
whereas this distribution was more compact in 2008. It was also observed that in 2008
the central tendency is located in the Southern-most part of the study area whereas
during recent period shifted to the Northern side. Species associated with L. inermis
were all mid- level carnivores similar to the species indicating a trophic cascading
happening in the Arabian Sea.
Keywords :
GIS tools, Spatial indicators, Abundance, Trophic cascading, Ecosystem management