An Evaluation of Economic Impact on Juvenile Landings of Cephalopods in Mumbai Waters, Northwest Coast of India

Abstract

Economic assessment of juvenile landings of 5 dominant cephalopods at New Ferry Wharf (NFW) landing centre, Mumbai was carried out during January to December, 2013. Dominant cephalopod fishery recorded include one species of squid, Uroteuthis (P) duvaucelii, three species of cuttlefishes, Sepia elliptica, Sepia pharaonis, Sepiella inermis and a species of octopus, Cistopus indicus together contributing 98% of total cephalopod landings. Estimated total annual economic gain calculated using bioeconomic model was Rs. 33.22 crores with estimated biomass gain of 4995 t per annum, if juveniles are allowed to grow up to length at first maturity (Lm)/Lmean. Among five species, C. indicus contribute maximum with 64.07 % of average juvenile catch followed by U. (P) duvaucelii (26 %), S. elliptica (23.63 %), S. inermis (23.27 %), and S. pharaonis (12.85 %). On these resources, while in S. inermis, both LM equals Lmean indicates breakeven point for the species. The study revealed that peak spawning season of these species coincides with peak juvenile landings which may result in reduction of overall size range thus will lead to loss of fishery in economic as well as ecosystem regime. The study indicates the improvement of harvest biomass by 2.95 times which would result in generating additional revenue to the fishers by a margin of 3.71 times; if juveniles are allowed to grow up to Lm/ Lmean whichever is greater.

An Assessment on Economic Impact of Growth Over Fishing of Commercially Important Marine Ariids Along Mumbai, Northwest Coast of India.

“…7,9,13,19 The utilization of low value bycatch (LVB) over the period in Indian coast increased from 14% in 2008 to 25% in 2011, this increasing trend was due to increase in price and demand for LVB for the production of fish meal and fertilizer. 11,12 In India, the literature reveales that very few It is evident from this study that juveniles are found abundant during the period between November to March which agrees with the findings by Kamei et al (2013) 14 and Sugumar et al (2015). 28 The inshore and coastal waters from southern Saurashtra to Ratnagiri may act as feeding ground for most of the dominant commercial important species during these months.…”

“…11,12 In India, the literature reveales that very few It is evident from this study that juveniles are found abundant during the period between November to March which agrees with the findings by Kamei et al (2013) 14 and Sugumar et al (2015). 28 The inshore and coastal waters from southern Saurashtra to Ratnagiri may act as feeding ground for most of the dominant commercial important species during these months. Several authors 16,19,21 observed the prevalence of marine catfish ranged between 30 and 80 m depth and it coincided with the present study wherein depth range was found to be 10 -60 m for these species.…”

Growth overfishing of hilsa shad in Hooghly-Bhagirathi river system, India: Assessment and management implications

“…Diekert et al (2010) asserted that growth overfishing squanders large parts of the potential rents in fisheries as the value of an individual fish grows significantly with age in most of commercial fisheries. The works on economic loss through juvenile fishing (Najmudeen and Sathiadhas, 2008;Mohamed et al, 2009;Kamei et al, 2013;Sugumar et al, 2015Sugumar et al, , 2016 indicated that impacts of growth overfishing are severe in tropical fisheries and the management measures to tackle this issue are difficult to implement due to the greater probabilities of incidental harvesting of non-targeted species and size groups associated with multi-gear, multispecies characteristics of the fisheries coupled with the local socio-economic and political scenarios. The annual economic loss through juvenile fishing by motorised and mechanised marine fishing fleet of entire Indian coastline was estimated at US$ 19,445 million (Najmudeen and Sathiadhas, 2008) which provides insight to severity of the issue in tropical fisheries.…”