An Agent-Based Model comprising a fish stock, a fishing fleet and a fish market is used to investigate the combined effects of environmental and market variability on the structure of a fishery. Over 15-year simulations, agents make daily fishing decisions and annual entry, exit, and investment decisions based on the fishery's past economic outcomes and their individual risk preferences and opportunity costs (e.g., an alternative source of income). Environmental variability is simulated through fishing success variability while market variability is simulated through changes in the elasticity of the demand curve (i.e., the responsiveness of market prices to changes in daily landings). Our findings indicate that changes in variability lead to changes in economic and biological conditions of the fishery by influencing the composition of risk preferences within the fleet. Counter to expectations, market stability did not dampen the negative impacts of environmental variability but rather stimulated over-investment and increased harvesting by a small number of risk-seeking fishers. Results from this research suggest that climate-driven increases in fisheries variability, coupled with increases in market integration that act to reduce local price signals, may lead to inefficient investments and reduced fishery resources.

中文翻译：

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模拟环境和市场变化对渔业结构的影响

基于代理的模型包括鱼类种群、捕捞船队和鱼类市场，用于研究环境和市场变化对渔业结构的综合影响。在超过 15 年的模拟中，代理人根据渔业过去的经济成果及其个人风险偏好和机会成本（例如，替代收入来源）做出每日捕捞决策和年度进入、退出和投资决策。环境可变性是通过捕捞成功率可变性来模拟的，而市场可变性是通过需求曲线弹性的变化（即市场价格对每日上岸量变化的反应）来模拟的。我们的研究结果表明，可变性的变化通过影响船队内风险偏好的构成而导致渔业经济和生物条件的变化。与预期相反，市场稳定并没有抑制环境变化的负面影响，反而刺激了少数寻求风险的渔民过度投资和增加捕捞。这项研究的结果表明，气候驱动的渔业变异性增加，加上市场一体化的增加，降低了当地价格信号，可能导致投资效率低下和渔业资源减少。市场稳定并没有抑制环境变化的负面影响，反而刺激了少数寻求风险的渔民过度投资和增加捕捞量。这项研究的结果表明，气候驱动的渔业变异性增加，加上市场一体化的增加，降低了当地价格信号，可能导致投资效率低下和渔业资源减少。市场稳定并没有抑制环境变化的负面影响，反而刺激了少数寻求风险的渔民过度投资和增加捕捞量。这项研究的结果表明，气候驱动的渔业变异性增加，加上市场一体化的增加，降低了当地价格信号，可能导致投资效率低下和渔业资源减少。