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Vulnerability of each stock in the catches from trawl fisheries in the Gulf of Thailand was assessed by productivity susceptibility analysis. Separate assessments were made based on type of trawler (otter-board, pair and beam) and vessel size (SS, S, M, L and XL, according to gross tonnage). Catches were distinctly different among trawler types and were dominated by demersal fishes, pelagic fishes and shrimps in the otter-board, pair and beam trawlers, respectively. The stocks of over 200 taxa were included in the study; high-vulnerability taxa were found for all trawl types and sizes, except the beam trawler size S. Only seven (7) taxa were classified as high vulnerability, including four (4) teleost taxa, namely Saurida elongata, Plotosus spp., Gymnothorax spp. and Sphyraena spp., and three (3) elasmobranch taxa, namely Carcharhinus spp., Brevitrygon heterura and Neotrygon kuhlii. Meanwhile, as many as 26 high-medium vulnerability taxa were found in catches by otter-board trawler size L, which included not only fishes but also cephalopods. Trends and variation in fish landings of 20 high and high-medium vulnerability taxa were analyzed. Eighteen (18) taxa showed monotonic trends, both continuous and discontinuous, in their time series of annual landings, but not Muraenesox spp. nor Uroteuthis spp. The long-term variations in fish landings ranged mostly between 40% and 50%. The short-term variations showed positive absolute and relative skewness, i.e., mostly between 10% and 20%. Results of this study highlight the taxa that require a precautionary approach for fishery management and warrant comprehensive fish stock assessment. Such data will allow more accurate determination of their status compared to the reference points and facilitate better management of trawl fisheries in the Gulf of Thailand. [ABSTRACT FROM AUTHOR]

Fixed closure (FC) is a standard fisheries management tool for protecting sensitive species or species requiring conservation. However, an FC might not effectively manage migratory species because of the large uncertainties of their migration. Adaptive real-time closure (ARTC) is a tool that updates closure areas according to the latest information. This study aimed to evaluate the effectiveness of ARTC to conserve sensitive species for data-limited fisheries by a series of simulations using migration models with hotspots. In the single species simulation, the conservation ratio for the sensitive species in FC varies widely at greater migration uncertainty. In ARTC, a longer duration of a hotspot resulted in a higher conservation ratio. When the mean duration of hotspots was medium or long, the conservation ratio for the sensitive species was more than 50 % in more than 99 % of the simulation trials. In multispecies fisheries, a clear trade-off was observed between the conservation ratio of sensitive species and other species. ARTC was more effective than whole closure when the proportion of sensitive species was high or without closure when the proportion was low. Conditions in which ARTC was most appropriate were described for hotspot duration, increased numbers of individuals in a hotspot, and the relative value of conservation, representing the ratio of the value of conserving sensitive species to one of catching other species. [ABSTRACT FROM AUTHOR]

Fish aggregating devices (FADs) used in the Gulf of Thailand are made of bamboo poles, twisted wire and coconut leaves, fastened to a concrete block. Purse seines with 2.5 cm mesh size are used to surround the fish, using fishing boats ranging from 18 to 26 m in overall length. Fishing grounds are located in the central Gulf of Thailand at a depth of 25–60 m. Catch per unit effort (CPUE), species composition and size of economically important species were analyzed by collecting data from fishing boats using FADs at nine main fishing ports along the Gulf of Thailand between January and December 2007. The results show that the average CPUE was 3351 kg day-1, which was composed of 88% pelagic fishes, 5% demersal fishes, 4% trash fishes and 2% squids and cuttlefishes. The major pelagic species were Indian mackerel (Rastrelliger kanagurta), Indian scad (Decapterus russelli) and bigeye scad (Selar crumenophthalmus), which made up 25%, 24% and 8% of the total catch, respectively, while neritic tunas (kawakawa; Euthynnus affinis, frigate tuna; Auxis thazard thazard and longtail tuna; Thunnus tonggol) made up 8% of the total catch. The mean length of ten economically important species was smaller than their size at first maturity, while two species were above their size at first maturity. The results indicated that juvenile fish were mostly being caught by FAD fishery, and this may lead to depletion in fisheries resources and economic loss. Although there is a set of measures to control the use of purse seines, effective management of the FAD capacity is also urgently needed. [ABSTRACT FROM AUTHOR]

Marine fishery is an economically important sector and the primary source of livelihood for coastal fishers in Thailand, but the open access harvesting system and overfishing have depleted fish stocks. The country should address both the issues to sustain a healthy marine fishery and protect the lucrative export market as well as to maintaining seafood self-sufficiency. This paper explains the on-going processes of implementing the measures of restricting the number and size of fishing vessels and fishing efforts to control fishing capacity. The marine resources in the Gulf of Thailand and the Andaman Sea are categorized into three separate species groups: (1) demersal, (2) pelagic, and (3) anchovies. The precautionary approach is used as the guiding principle, and maximum sustainable yield (MSY) of the three combined resource categories is used as a reference point in setting the total allowable catch (TAC) limits in this exercise. The number of fishing days per vessel per year is stipulated by issuing licenses based on the TAC size and total allowable effort (TAE). Both the advantages and disadvantages of the current fishing allocation system are discussed. [ABSTRACT FROM AUTHOR]

Fisheries resources play a crucial role in economic development, food security, and healthy nutrition for humans. Consequently, fisheries are of paramount importance for several Sustainable Development Goals, in particular SDGs 1 and 8, which are related to poverty and economic growth, as well as SDGs 2 and 3, which are about zero hunger and good health. On the other hand, fisheries can also negatively influence the ecosystem (SDG 14, life below water). Thailand is one of the world's most significant producers and exporters of fisheries products. This present work describes the evolution of wild fisheries production in Thailand for over twenty years and discusses its impact on fish and shellfish supplies. The present overview uses mainly the official statistical catch data of Thailand. From 1995 to 2015, Thailand's marine fisheries production gradually decreased from approximately 2.8 million tonnes to 1.3 million tonnes per year. Concerning taxonomic composition of the catches, no dramatic shifts were recorded during the 20-year period. The main observation seems that for less abundant taxa, such as Chirocentridae, Sillaginidae, Ariidae, Sharks, and Psettodidae, their part in the catch was halved between 1995 and 2015. On the other hand, inland capture fisheries remained constant at 0.2 million tonnes per year. The annual value of wild fisheries production was, on average US$1.7 billion. Notably, trawl fishing systematically reduced during these two decennia, resulting in a fishing efficiency of approximately 140 tonnes of demersal fish per trawl unit per year in 2015. During 2008–2015, the number of registered gill net fishing boats drastically increased from 2,300 to 6,600, and this has led to a dramatic decline in fishing efficiency to about 10% in 2014–2015. More in general, Thailand's continuous decline in marine capture production was linked to increased fuel prices, tightening restrictions by neighbouring countries for access into their exclusive economic zone, and the depletion of resources due to overfishing and illegal fishing. Against rising concerns about the sustainability of intensive fishing practices in recent years, Thailand is ramping up efforts to reduce the exploitation of fishery resources to levels that would achieve maximum sustainable yields. In particular, the intensity of fishing based on gill nets needs to be addressed in the future. Hence, Thailand's fisheries production faces the pressure of realising the importance of sustainable fisheries resources management and its impact on marine life and biodiversity, in addition to its role as a significant food source for a healthy population. [ABSTRACT FROM AUTHOR]