Not Available ; Potential Fishing Zone (PFZ) advisory maps released by the INCOIS (Ministry of Earth Sciences, Government of India) during 2003-07 were analyzed for their frequency of occurrence and persistence. This analyses clearly indicates that the nearshore regions of the Arabian Sea off Kerala with depths less than 50 m occurred more in the PFZ advisory maps than the mid continental shelf region and the continental slope. Northen regions of Kerala had persistent PFZ areas especially in the region between Calicut and Kannur. Relatively high river discharges in the area and presence of high nutrient content in the discharges because of high mangrove afforestation are likely causes for the persistent occurrence of PFZs in these regions. ; Not Available
Not Available ; India ranks third in global fish production with 6.4 million metric t, but mariculture in the Indian seas is yet to be popularised. The limited availability of protected sites and the probable conflicts with other activities such as fishing, tourism and navigation are factors likely to influence mariculture development in India, besides finance, technology, expertise and government policy. A pilot scale inshore marine cage culture experiment has been undertaken since 2007 at Visakhapatnam coast of India in the Bay of Bengal. A similar cage was launched at Munambam for the culture of Asian seabass Lates calcarifer. Asian seabass seed (3.5 ±1.5 g) reared in hapa installed in ponds for a period of 30 days were stocked in the cage and cultured for a period of 120 days and harvested at an average weight of 315.5 g. Analysis of nutrient levels in seawater near the cage, revealed no noticeable accumulation of solid particulate wastes indicating that water current (0.5 to 1.0 m sec-1) was adequate in the site to prevent accumulation of wastes in the cage as well as in the premises. The cage culture activity was found to influence the planktonic and benthic fauna. ; Not Available
Not Available ; In India, the adoption of mussel (Perna viridis) farming, practice began in 1996 when it was field tested in the shallow backwaters of Padanna in Kasaragod District of Kerala. This paved the way for commercial mussel production from northern districts of Kerala, particularly in Padanna Backwaters by coastal villagers. There was a steady rise in mussel production from estuarine farms till 2008, which was followed by a reduction since 2009. During 2015, this rate of reduction in farmed mussel production was drastic, recording as high as 93.8%, when compared to the 2014 figures. This reduction was not restricted to Padanna Backwaters alone, as there was mortality and decline in production in all northern districts of Kerala in 2015. Mussel farming sector of Padanna Backwaters is confronted with several problems. With rapid growth in farming the availability of mussel seeds became limiting and farmers sourced seeds from distant locations resulting in poor seed quality at the time of seeding. The supply-demand gap pushed the farmers to compromise on the seed quality. This resulted in tended mussel stocks which were susceptible to stress. The environmental degradation in the farmed area of Padanna due to excessive number of farms per unit area and reduced flushing of water in certain pockets was further burdened by the extremely high ambient air and water temperatures in 2015-16. The prevailing environmental anomaly resulted in higher than normal salinity and high temperature, which compounded the environmental stress on the farmed mussels. This resulted in a crisis in February 2016, leading to stunted growth, high mortality and prevalence of the protozoan parasite, Perkinsus olseni. The CMFRI's scientific team which has been monitoring the mussel farming activity in the area, setup a task force to identify the issues and suggest solutions to farmers and the Government. The adoption of sustainable aquaculture practices in Padanna Backwaters by improving the quality of seeds, enhancing the flushing rates, modifying the farm layout and reducing the farming density per unit area are among the 21 recommendations proposed by CMFRI task force to tackle these challenges. These recommendations are complementary to the global guidelines for Best Aquaculture Practices for mussels. This requires the collaborative effort from the farmers, local administration and the fisheries department. ; Not Available
