Welfare impact of climate change on capture fisheries in Vietnam

primarily owing to the growing population and improving income, consumers may benefit if the demand surpasses a certain level. However, the latter case is not likely to happen since aquaculture is escalating rapidly, and consumption is more likely to shift from wild to farmed fish. In contradiction to many concerns that climate change will affect producers adversely as it reduces capture revenues [27, 29, 36, 85], the research results find that fishers gain more than lose thanks to the price upsurge if the demand for wild fish remains unchanged. If there is no price increase, i.e., demand for wild fish decreases as farmed fish is more available, the fisher’s profit reduces 20%–24% of their profit in 2018 by 2035 and 35%–46% by 2065. The loss of profit is from 1.0 to 1.3 billion USD (PPP, 2018). Since the consumer preferences on wild fish and farmed fish are different for individuals, it is not likely that farmed fish can fully replace wild fish. Hence, fishers have more chance to benefit than lose. These findings suggest that although climate change hinders fishing production, fisher’s welfare is more likely to increase, and consumer welfare is more likely to decrease. In Vietnam, the capture fishery sector is a pro-poor economic sector. The fishery policies usually aim to maximize social welfare, helping people escape poverty. Therefore, wild fish is open access, leading to the spread of small-scale fishers along the seaside, escalating stress on nearshore fish stock. No specific actions limiting small-scale capture have been implemented

in the Vietnam fishery sector. The application of quotas for inshore and offshore fishing ves- sels, newly introduced since 2019, is controversial and faces many obstacles, especially from fishers. The research findings imply that limiting capture effort do not harm fishers’ welfare in the long run. The Vietnam Fisheries Development Strategy for 2021-2030 [31] sets its goals to develop aquaculture, especially marine species, as an adaptation action for dealing with the reduction of capture. However, saline aquaculture is often achieved by over-fishing wild juveniles and stocks to serve as food for cultivated species [86]. Therefore, the impact of expanding aquacul- ture on capture remains ambiguous. Furthermore, the change in wild fish demand remains uncertain. More research is needed to understand how aquaculture expansion could impact capture producers’ income, employment, and profits. Supporting information S1 Data. 1 (RAR) Author Contributions Conceptualization: Thi Vinh Ha Nguyen. Data curation: Thi Vinh Ha Nguyen. Formal analysis: Thi Vinh Ha Nguyen. Methodology: Thi Vinh Ha Nguyen. Project administration: Thi Vinh Ha Nguyen. Resources: Thi Vinh Ha Nguyen. Software: Thi Vinh Ha Nguyen. Supervision: Thi Vinh Ha Nguyen. Validation: Thi Vinh Ha Nguyen. PLOS ONE Welfare impact of climate change on capture fisheries in Vietnam PLOS ONE | https://doi.org/10.1371/journal.pone.0264997 April 25, 2022 16 / 20