A decision tree analysis to support potential climate change adaptations of striped catfish (Pangasianodon hypophthalmus Sauvage) farming in the Mekong Delta, Vietnam

This study uses the decision tree framework to analyse possible climate change impact adaptation options for pangasius (Pangasianodon hypopthalmus Sauvage) farming in the Mekong Delta. Here we present the risks for impacts and the farmers' autonomous and planned public adaptation by using primary and secondary data. The latter studies showed that a proportion of the pangasius farms located in the coastal provinces will be affected by salinity intrusion in the dry season. Options to adapt to this are: modify pangasius farming practice, stock other species or stock saline-tolerant pangasius. With research and extension support, farmers can further improve their already adapted practice to deal with salinity or use water recirculation systems for prolonged nursery rearing. A breeding program for saline-tolerant striped catfish requires a medium-to long-term investment (0.4 % of the production cost) from government and/or private company. Pangasius farms in up- and mid-stream regions and in coastal areas, which are not located within upgraded government dyke-protected areas, will be affected by flooding at the end of each rainy season. This implies an increased cost for dykes to about 0.34% and 0.25% of the total variable costs for one harvest per ha in the up- and mid-stream regions, and in the downstream region, respectively.