Impact of endogenous and exogenous factors on catches: A case study of Vietnam’s offshore fisheries

Abstract

The performance of fishing vessels is influenced by both endogenous and exogenous factors. This study aims to investigate the impact of these factors on the catch quantity of offshore gillnet vessels in Khanh Hoa, Vietnam, by estimating the harvest function using survey data from three fishing seasons (2008, 2013, and 2018). The study has revealed that endogenous factors, such as engine capacity, the number of nets, the number of fishing days, and variable costs, exhibit a positive impact on catches at the 1% level of significance. Among these factors, the number of nets has the highest effect on catches. Nevertheless, the effect coefficients are generally smaller compared to those observed in previous studies within the same area or on the same fishing grounds. Conversely, the coefficient estimate for the age of the vessel owner is negative, though statistically insignificant. Exogenous factors manifest varying effects on the quantity of catches. The research result found no discernible effect of fuel cost support, while the stock proxy exhibited a minor impact coefficient, and climate change awareness had a noteworthy impact on catch quantities at the 1% level of significance. The findings imply that offshore resources could be experiencing a growing scarcity. Additionally, as fishermen's awareness of climate change increases, they might be more inclined to adjust and manage its impacts. Moreover, it raises concerns about the long-term sustainability of open-access fisheries that rely on subsidies. The study suggests that fishing policies should focus on regulating offshore vessels' input factors to prevent the overuse of offshore resources. In addition, policies should support fishermen in adopting appropriate coping strategies when faced with climate change. Furthermore, subsidy policies that do not harm offshore resources should be promoted.