Small-scale fisheries are critically important for livelihoods around the world, particularly in tropical regions. However, climate variability and anthropogenic climate change may seriously impact small-scale fisheries by altering the abundance and distribution of target species. Social relationships between fishery users, such as fish traders, can determine how each individual responds and is affected by changes in fisheries. These informal cooperative and competitive relationships provide access, support, and incentives for fishing and affect the distribution of benefits. Yet, individuals’ actions and impacts on individuals are often the primary focus of the economic analyses informing small-scale fisheries’ formal management. This focus dismisses relevant social relationships. We argue that this leads to a disconnect between reality and its model representation used in formal management, which may reduce formal fisheries management’s efficiency and efficacy and potentially trigger adverse consequences. Here, we examine this argument by comparing the predictions of a simple bioeconomic fishery model with those of a social-ecological model that incorporates the dynamics of cooperative relationships between fish traders. We illustrate model outcomes using an empirical case study in the Mexican Humboldt squid fishery. We find that (1) the social-ecological model with relationship dynamics substantially improves accuracy in predicting observed fishery variables to the simple bioeconomic model. (2) Income inequality outcomes are associated with changes in cooperative trade relationships. When environmental temperature is included in the model as a driver of species production dynamics, we find that climate-driven temperature variability drives a decline in catch that, in turn, reduce fishers’ income. We observe an offset of this loss in income by including cooperative relationships between fish traders (oligopoly) in the model. These relationships break down following species distribution changes and result in an increase in prices fishers receive. Finally, (3) our social-ecological model simulations show that the current fishery development program, which seeks to increase fishers’ income through an increase in domestic market demand, is supported by predictions from the simple bioeconomic model, may increase income inequality between fishers and traders. Our findings highlight the real and urgent need to re-think fisheries management models in the context of small-scale fisheries and climate change worldwide to encompass social relationship dynamics.

小规模渔业对世界各地的生计至关重要，特别是在热带地区。然而，气候变率和人为气候变化可能通过改变目标物种的丰度和分布而严重影响小规模渔业。渔业用户之间的社会关系，例如鱼贩，可以决定每个人如何应对渔业变化并受到渔业变化的影响。这些非正式的合作和竞争关系为捕鱼提供了准入、支持和激励，并影响了利益的分配。然而，个人的行为和对个人的影响往往是经济分析的主要焦点，为小规模渔业的正式管理提供信息。这种关注忽略了相关的社会关系。我们认为，这导致现实与其在正式管理中使用的模型表示脱节，这可能会降低正式渔业管理的效率和功效，并可能引发不利后果。在这里，我们通过比较简单的生物经济渔业模型的预测与结合了鱼类贸易商之间合作关系动态的社会生态模型的预测来检验这一论点。我们使用墨西哥洪堡鱿鱼渔业的实证案例研究来说明模型结果。我们发现（1）具有关系动态的社会生态模型显着提高了预测观察到的渔业变量对简单生物经济模型的准确性。(2) 收入不平等的结果与合作贸易关系的变化有关。当模型中包含环境温度作为物种生产动态的驱动因素时，我们发现气候驱动的温度变化会导致捕捞量下降，进而减少渔民的收入。我们通过在模型中包含鱼类贸易商（寡头垄断）之间的合作关系，观察到这种收入损失的抵消。这些关系随着物种分布的变化而破裂，并导致渔民获得的价格上涨。最后，（3）我们的社会生态模型模拟表明，当前旨在通过增加国内市场需求来增加渔民收入的渔业发展计划得到了简单生物经济模型预测的支持，可能会增加渔民之间的收入不平等和贸易商。