The sustainable livelihood approach is an analytical framework that helps identifying the assets that local communities rely on, the risks they are subjected to, organisations and institutions influence their daily lives and the strategies they undertake. This is a valuable approach in small-scale fisheries management as artisanal fisheries are exposed to uncertainty in terms of supply and demand, and fishing activities usually are influenced by social and institutional factors. However, in spite of its usefulness and the fact that this approach has been previously used in projects targeting small-scale fisher communities, it is still not widely applied to small-scale fisheries. In this study we applied the sustainable livelihood approach as an analytical tool to assess the potential of the mud crab Scylla serrata as a sustainable livelihood resource for the southwest Indian states such as Karnataka. As fishers worldwide face continuous pressure from industrial fishing fleets and decreased fish stocks and their productivity, we also identified what could be the potential barriers to small-scale mud crab farming for communities that are already are involved in mud crab fishing. Data were collected and analysed from a semi-structured questionnaire, two focus group discussions and key informant interviews conducted in Uttara Kannada district, Karnataka. The results indicated that though mud crab is perceived as a good source of income in this area, at present it is not recognised as a steady source of income due to the unpredictable fishery catches. Respondents were aware of mud crab farming yet stated the lack of land and financial resources as the main barriers and only the minority expressed any interest in undertaking such activity. The sustainable livelihood approach proved to be a valuable research tool for identifying matters of concern for local communities regarding their source of livelihoods and barriers to small-scale aquaculture.

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Research characterising the effects of future climate change on the marine environment remains heavily focussed on that of temperate regions and organisms. Furthermore, little is known of these effects on the early life stages of many marine species. Tropical regions are already experiencing an increase in sea surface temperature and decrease in sea surface salinity, conditions favoured by pathogenic bacteria such as Vibrio spp. The early life stages of crabs are known to be particularly vulnerable to both the direct physiological effects of climate change and exposure to harmful microorganisms, yet there are limited data on these effects on juveniles of many tropical crustacean species. This study assessed the metabolic responses of mud crab (Scylla serrata) juveniles to warming and/or freshening in the presence or absence of pathogenic bacteria in southwest India. Juvenile crabs were exposed to either ambient (28 °C/30 PSU) or one of three projected climate change regimes (28 °C/20 PSU (freshening), 32 °C/30 PSU (warming), 32 °C/20 PSU (warming + freshening)) for 10 days, in either the presence or absence of the pathogenic bacteria Vibrio parahaemolyticus. Results show that simulated climate change conditions, especially freshening, caused a significant increase in oxygen consumption rates (MO2), and that these were further increased when juveniles were exposed to V. parahaemolyticus. These results suggest that the effects of future climate change conditions could have significant implications for the conservation of wild stocks and commercial farming of this species in South Asia.