The dynamic coastline of Soc Trang Province in the Mekong Delta of Viet Nam is in most parts protected from erosion, storms and flooding by a narrow belt of mangroves. However, the unsustainable use of natural resources and development in the coastal zone is threatening the protection function of this forest belt. This situation is exacerbated by the impacts of climate change, particularly by the increased intensity and frequency of storms, floods and by rising sea levels. Based on analysis of past experience of mangrove planting and historical changes in mangrove cover, an integrated and site-specific approach to adaptation to climate change has been put in place, which comprises mangrove planting and rehabilitation with emphasis on resilience to climate change, and participatory involvement of local communities in effective mangrove management and protection through co-management. To address uncertainties associated with the impacts of climate change, testing of new mangrove planting techniques has started. This includes mimicking successful natural regeneration for small-scale planting in sites with high wave energy and transformation of existing even-aged plantations into more diverse forests-both in terms of structure and species composition. The pre-requisite for mangrove rehabilitation in erosion sites has successfully been put in place: breakwaters made from bamboo have reduced erosion and stimulated sedimentation. The design and construction of the wave-breaking structures, which was based on a numerical model which simulates hydrodynamics and shoreline development, ensures that downdrift erosion can be avoided as far as possible. A comprehensive monitoring program has been established and initial results provide evidence for the effectiveness of the bamboo breakwaters. Early experience shows that co-management is an effective way of maintaining and enhancing the protection function of the mangrove forest belt and at the same time providing livelihood for local communities. Payment for ecosystem services contributes to sustainability of co-management as well as livelihood improvement.

It has been proposed that sympatric bumblebee species form mimicry rings to profit from learnt avoidance behaviour by predators. This hypothesis can be tested by comparing the predation rates of local bumblebees with those of imported nonnative bumblebees, whose coat colour is different from that of local bees, so that their coloration is unfamiliar to local predators. To test whether populations of non-native bumblebees suffer higher worker loss rates during foraging, we conducted transplant experiments in the UK, Germany and Sardinia. The loss rates of foraging workers of four Bombus terrestris populations (Bombus terrestris canariensis, Bombus terrestris terrestris, Bombus terrestris sassaricus and Bombus terrestris dalmatinus) were compared, evaluating data from 989 foragers, whose flight times were monitored precisely (over 8258 h of foraging). While all of these workers display a bright UV-reflecting abdominal tip, the colours in other body parts differ strongly to the eyes of avian predators. The hypothesis that foragers from the non-native bumblebee populations, which differ in coloration from the local native population, would suffer higher predation risk was not upheld. In contrast, in one location (Sardinia) the native population had the highest loss rate. The consistent population rank order we found in terms of forager losses indicates that such losses are more prominently affected by factors other than the familiarity of local predators with aposematic colour patterns.

Many coastal areas throughout the world are at risk from sea level rise and the increased intensity of extreme events such as storm surge and flooding. Simultaneously, many areas are also experiencing significant socio-economic challenges associated with rural-urban transitions, population growth, and increased consumption resulting from improving gross regional product. Within this context we explore the viability of proposed adaptation pathways in Soc Trang province, Vietnam-an area of the Mekong Delta experiencing cumulative pressures on coastal livelihoods. A participatory workshop and interviews, using a combination of systems thinking and futures techniques, revealed a shared goal of sustainable livelihoods, which provides an integrated and systemic focus for coastal adaptation strategies. Emphasizing sustainable livelihoods is less likely to lead to maladaptation because stakeholders consciously seek to avoid optimizing particular system elements at the expense of others-and thus engage in broader decision-making frameworks supportive of social-ecological resilience. However, the broad ambit required for sustainable livelihoods is not supported by governance frameworks that have focused on protective strategies (e.g., dyke building, strengthening and raising, to continue and expand agriculture and aquaculture production) at the expense of developing a diverse suite of adaptation strategies, which may lead to path dependencies and an ultimate reduction in adaptive capacity for system transformation.

The dynamic coastlines in the Lower Mekong Delta of Vietnam are threatened by the impacts of climate change, particularly by the increased intensity and frequency of storms and floods, as well as by rising sea levels. The most effective coastal protection systems consist of different elements arranged in series, for instance natural floodplains vegetated with mangroves and a sound dyke line. However, the unsustainable use of natural resources and development in the coastal zone are threatening the protection function of the mangrove forest belt. In sites where severe erosion has destroyed the mangrove belt, restoration of floodplains and mangrove rehabilitation is only possible after the wave energy has been reduced by physical barriers. This can be achieved with bamboo fences, which reduce erosion and stimulate sedimentation. Restoration of the eroded floodplains creates the preconditions for rehabilitation of the destroyed mangrove forest. Mangrove management is an important element of an area costal protection strategy.

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This case study looks at changing livelihood strategies of the coastal population in Soc Trang Province in the Mekong Delta, Vietnam, and their impacts on natural resources. It provides an opportunity not only to document the impact of shrimp farming on coastal livelihood but also to better understand the link between brackish water aquaculture development and natural resource use. The approach includes a socioeconomic survey in six villages of the province focusing on risk strategies and livelihood diversi¢cation. Shrimp farming was found to be less risky and more pro¢table for households and private companies with a higher investment capacity than for poorer households. Households facing a high risk in shrimp farming diversi¢ed their aquaculture production, with other high-value species like mud crab and elongated goby as a coping mechanism. The use of natural resources'collection is shifting from home consumption towards market-oriented sales of juvenile mud crabs, clams or ¢sh (elongated goby) to supply seed for brackish water aquaculture developments.

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