KOCHI: A biomass dynamics modelling study carried out on 223 fish stocks of 41 marine fishery resources of India under a multi-gear and multispecies fishery situation revealed that 79 fish stocks are overfished. The study published in the ICES Journal of Marine Science says that it is necessary to reduce the total annual fishing hours of nine different categories of fishing fleets harvesting marine fishery resources.
The study aimed to derive an understanding for management requirements of 223 commercially-important fish stocks in different maritime states of India. Two decades (1997-2016) of fishery-related data on the harvest of resources by different types of fishing fleets were used and a gear-standardization parameter was used for the analysis.
In this category of overfished and overfishing, the main marine species caught include Indian oil sardine, mackerel, anchovies black pomfret, catfishes, crabs, frigate and bullet tunas, penaeid prawns, threadfin breams, wolf herring, etc, which are common across all maritime states.
“Such models are used worldwide to study sustainability and management. However, unlike elsewhere, in our water, we have a vast diversity in species as in the fishing gear used. A need for such a study arose after the huge fall in catch of Indian oil sardines. Each maritime state had shown a drop in largely caught local species,” said Sunil Mohamed, fisheries scientist and one of the authors of the study.
The team of researchers from Central Marine Fisheries Research Institute (CMFRI) did the analysis using the time-series of landings of species, fishing gears and total landings. The results indicate that 34.1% of the assessed fish stocks in India are sustainable, 36.3% are overfished, 26.5% are recovering, and 3.1% are in the overfishing status.
“One of the challenges was incorporating the multi-gear nature of fishing into the model. We solved it by introducing a gear standardization parameter,” said CMFRI ex-principal scientist Mohamed.
The highest percentage of sustainable fish stocks were in Goa (63.6), West Bengal (52.6) and Kerala (52%), the highest percentage of overfished stocks were in Puducherry (71.4%), Gujarat and Daman Diu (65%) and Maharashtra (46.4%), and the highest percentage of recovering fish stocks were in Andhra Pradesh (50%), Odisha (40.7%) and Maharashtra (32.1%).
