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This study was conducted to assess the status of small-scale artisanal sea cucumber fishing around the islands of Phu Quoc, Nam Du, and Hai Tac, located in Kien Giang Province, Vietnam. A total of 90 sea cucumber fishers were randomly interviewed from October 2018 to March 2019. Results indicate that most fishers (96.7%) consider sea cucumber fishing as an extra income and use simple fishing methods such as diving (free diving and snorkeling), gleaning, and scoop nets. Catch composition (% whole wet weight) comprises five species, of which low- and medium-value species are most commonly harvested, including Holothuria leucospilota (39.5%–58.2%) and Stichopus spp. (29.7%–48.4%), followed by Holothuria atra (7.3%–10.9%) and two high-value species that are rarely found, that is, Holothuria scabra (2.6%–6.6%) and Holothuria nobilis (1.2%–1.6%). Current catch rates for an average fishing trip are 25.8–37.6 kg wet weight per diver, which has declined by 60%–95% over the past 10 y, indicating heavy overexploitation. Currently, the exploitation of sea cucumber in Kien Giang has encountered some difficulties, such as unusual weather, the drastic depletion of high-value stocks, and unstable selling price. This information will be useful for further research related to planning effective management programs for sea cucumber fisheries in the region.

This study was carried out from February to December 2014 by interviewing 75 farmers who operate snakehead seed production in An Giang, Dong Thap and Hau Giang provinces, Vietnam. The results showed that the total area for production was 629.01±756.77 m2, whereas the volume for nursing was 582.10±119.81 m3 for pond system and 1,019.56±736.66 m3 for combining pond – hapa system). Each hatchery used 44.26±22.63 pairs of broodstock/breeding cycle and produced whole year. The quantity of seed per cycle of pond system was a half of that figure of other system while seed productivity per m3 was much lower. Snakehead seed was mainly sold to seed traders in the Delta (82.3%). With average production cost of 47.81±16.23 thousand Vietnam dong (VND)/m3, each farm in pond system could reach the total net profit of 49.83±18.74 thousand VND/m3, equivalent to 328 million VND/year. These corresponding numbers of pond – hapa system were 106.98±86.25; 196.12±87.45 thousand VND/m3, equal to 1.75 billion VND/year. Factors of climate change affecting snakehead seed production involved rainfall change, droughts, water and air temperature increase, salinity intrusion which caused diseases easier (36%), affected seed production in general (31%), bad water quality (10%), .... To reduce the impacts of climate change to production, the farmer in snakehead seed production often changed selling market, suspended production of seeds, used better brookstocks by choosing them more carefully and a number of other measures.

This work examined diet composition of the juvenile orange-spotted grouper, Epinephelus coioides, and its trophic association with other juvenile fish species in tropical estuarine habitats during recruitment. From December 2015 to March 2016, juveniles were collected, their stomachs excised, preserved and analyzed. Small shrimps and amphipods, especially Grandidierella sp. and Elasmopus sp., were the most common food resources sharing among the most species. Epinephelus coioides predominantly ingested small shrimp, Grandidierella sp., Elasmopus sp. and fish larvae and had the greatest trophic overlap with Palatrus scapulopunctatus. Fish size, location and month significantly affected fullness indices and food items diversity in E. coioides. It is clear that the larger the size of E. coioides and its mouth opening, the larger the size of items ingested. This study confirms the ontogenetic dietary shift of juvenile E. coioides during recruitment season by starting as amphipod and small shrimp feeder and shifting to shrimp and fish larvae predator as they grow. This finding is fundamental to understanding how juvenile E. coioides cope with different conditions and its association with other co-existing species during the recruitment period.