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Silver pomfrets are spread along the Indo-West Pacific: from the Persian Gulf to Indonesia, Japan, West and Southwest of Korea and Eastern parts of China and forms a commercial fishery in all these countries. For formulating fishery management strategy of the silver pomfret, accurate population information is necessary. The genetic stock structure of silver pomfret in the Northern Indian Ocean was explored using 12 polymorphic microsatellite markers. Morphological and molecular studies confirmed that the silver pomfrets along the Northern Indian Ocean is Pampus candidus. Pampus candidus populations along Arabian Sea and Bay of Bengal region (FST =0.049, P

Akhiljith, P.J.; Liya, V.B.; Rojith, G.; Zacharia, P.U.; Grinson, G.; Ajith, S.; Lakshmi, P.M.; Sajna, V.H., and Sathianandan, T.V., 2019. Climatic projections of Indian ocean during 2030,...

Joseph, D.; Liya, V.B.; Rojith, G.; Zacharia, P.U., and Grinson, G., 2019. Time series analysis of CMIP5 model and observed sea surface temperature anomaly along Indian coastal zones. In: ...

Ajith, S.; Rojith, G.; Zacharia, P.U.; Nikki, R.; Sajna, V.H.; Liya, V.B., and Grinson, G., 2019. Production, characterization and observation of higher carbon in Sargassum wightii biochar from Indian coastal waters. In: Jithendran, K.P.; Saraswathy, R.; Balasubramanian, C.P.; Kumaraguru Vasagam, K.P.; Jayasankar, V.; Raghavan, R.; Alavandi, S.V., and Vijayan, K.K. (eds.), BRAQCON 2019: World Brackishwater Aquaculture Conference. Journal of Coastal Research, Special Issue No. 86, pp. 193–197. Coconut Creek (Florida), ISSN 0749-0208.Seaweed farming gains significance as a climate resilient strategy owing to significant carbon sequestration potential and research advances to valorize products from seaweed resources. Conversion of seaweeds to biochar enhances further carbon sequestration. In this study Sargassum wightii, belonging to brown algae has been converted into biochar under different conditions of pyrolysis for possible application in aquaculture sector. The prepared biochar was subjected to elemental (CHNS) analysis to assess the nutrient profile. Further, comparative analysis has been done on raw seaweed and biochar based on the structural characterization using SEM, XRD and FTIR spectra. Functional group changes were evidenced from FTIR and XRD spectra, whereas surface modifications were elucidated by SEM analysis. The optimum temperature for biochar pyrolysis of S. wightii to yield higher carbon content has been identified. A significant observation is that seaweeds in Indian coastal waters are capable of higher carbon sequestration than in other waters.

Sajna, V.H.; Zacharia P.U.; Liya, V.B.; Rojith, G.; Somy, K.; Joseph, D., and Grinson, G., 2019. Effect of climatic variability on the fishery of Indian Oil sardine along Kerala coast. In: Jithendran, K.P.; Saraswathy, R.; Balasubramanian, C.P.; Kumaraguru Vasagam, K.P.; Jayasankar, V.; Raghavan, R.; Alavandi, S.V., and Vijayan, K.K. (eds.), BRAQCON 2019: World Brackishwater Aquaculture Conference. Journal of Coastal Research, Special Issue No. 86, pp. 184–192. Coconut Creek (Florida), ISSN 0749-0208.Indian oil sardine (IOS), the commercially and ecologically important pelagic fish of the Kerala coast is susceptible to climatic variation. The study analyzes the impact of climate change on the catch of Sardinella longiceps along the Kerala coast and tries to predict the catch trend under the two RCP scenarios 4.5 and 6.0 for the period 2020-2100. Monthly catch of IOS by major gears for the period 1990-2016 was collected and Relative effort (Effort) and Weighted CPUE (cpue) were accordingly estimated. The climatic variables Sea Surface Temperature (SST), Precipitation (Pr), Chlorophyll a (SSC) and Salinity (SSS) were obtained from NOAA/NASA. The relationship of cpue and Effort of IOS to environmental variables were explored by Generalized Additive Model. The best fit model was selected using lowest Akaike information criterion (AIC) value, Deviance and F statistic. Predictions of cpue and Effort under RCP 4.5 and RCP 6.0 were done and the catch of IOS was estimated. The GAM model revealed the variations in the catch of IOS in relation to climate change. The SST, SSS and Pr showed a negative relation whereas SSC was found to be positively related to the catch of IOS. The results of the study indicate a decreasing trend of cpue and catch and an increasing trend of Effort towards 2100 under both climate change scenarios.

Genetic variation in wild stocks of a major commercial shrimp, Fenneropenaeus indicus, from the marginal seas in the Indian Ocean was analysed using polymorphic microsatellite loci and mitochondrial COI gene. The average observed heterozygosity (Ho = 0.44 ± 0.02) and the expected heterozygosity (He = 0.73 ± 0.01) were high across loci and populations indicating high microsatellite variation. Pairwise FST and Bayesian clustering indicated the occurrence of four genetically distinct stocks out of the eight sampled populations with implications for specific management approaches. Mantel test for isolation by distance proved that genetic differentiation is not related to geographic distance between populations. Mitochondrial COI sequence analysis showed concordant differentiation pattern as well indicated the relevance of COI in population genetics of shrimps. Pairwise ɸST and phylogenetic and Bayesian analyses revealed four distinct clades, as observed with nuclear markers. Divergence time analysis revealed the origin and initial divergence of F. indicus corresponds to late Miocene and divergence to phylogroups in the Pleistocene. BSP analysis presented a long stable population size with a slight decrease in the late Pleistocene and gradually expanded to the current status. The information here will be useful in commercial shrimp breeding and selection programmes and management of natural stocks of Indian white shrimp.

Sea Surface Temperature (SST) derived from the NOAA AVHRR satellite data were used to generate the Degree of Heating Weeks (DHW) and Hot Spot (HS) products. Combination of the cumulative temperature anomalies and the thermal stress studies were yielded to synoptically identify the probable areas of bleaching. The bleaching status of the Andaman region was assessed based on the DHW and HS for the bleaching event occurred in the Andaman region in April/May 2005. The bleaching status up to Alert Level-1 was recorded with the maximum HS of 3 o C and DHW 6 o C-week. Simultaneous in-situ reef observations conducted in the Andaman Sea confirmed the coral bleaching event. The maximum mortality in the region due to coral bleaching was shown by the Acropora species (43%) followed by Montipora species (22%) and Porites species (14%). This study focused on detection of coral bleaching warning based on the SST in compliment with the in-situ observations. Keywords: Andaman Island, Hot Spot, degree of heating weeks, thermal stress, sea surface temperature.

The Andaman coral reef region experienced mass bleaching events during 1998 and 2010. The purpose of this study is to investigate the role of the El Nino in the coral reef bleaching events of the Andaman region. Both Nino 3.4 and 3 indices were examined to find out the relationship between the mass bleaching events and El Nino, and correlated with sea surface temperature (SST) anomalies in the Andaman Sea. The result shows that abnormal warming and mass bleaching events in the Andaman Sea were seen only during strong El Nino years of 1997–1998 and 2009–2010. The Andaman Sea SST was more elevated and associated with El Nino Modoki (central Pacific El Nino) than conventional El Nino (eastern Pacific El Nino) occurrences. It is suggested that the development of hot spot patterns around the Andaman Islands during May 1998 and April–May 2010 may be attributed to zonal shifts in the Walker circulation driven by El Nino during the corresponding period.