Bioeconomic modelling of marine fisheries: Seeking keys to sustainable income for marine fishers of Mumbai, India

To address the issue of overfishing, sustainability and its effect on marine fishers’ income, this study was taken up in Mumbai, India. Greater Mumbai was studied at micro level. Primary data on capital costs, operating costs and returns to mechanized fishing were collected. Secondary data on marine fish landings, landings from the trawlers and total effort of trawlers was collected from 2000 – 2018. The Gompertz-Fox Model was used, and results showed that Maximum Sustainable Yield (MSY) was at 1,04,099 tonnes of fish and effort level corresponding to MSY (EMSY) at 43,363 fishing trips against the current 1,31,118 tonnes and 33,466 trips. Maximum Economic Yield (MEY) was calculated to be 1,03,030 tonnes, while the estimated value of effort (EMEY) was 37,429 trips. Therefore, the current fishing yield was found to be both biologically and economically unsustainable. The study concluded that the catch and income of fishers may be sustainably enhanced by following the MSY and MEY approach. Fishing at MEY will yield increased income in real terms as well as saved catch will ensure minimisation of environmental damage. Reducing the input costs will enable savings on wasteful operational costs, resulting in increased savings, which in other words, is income, since averted loss is income earned.