Abstract Small-scale fisheries provide vital food security for coastal communities worldwide, yet they face numerous challenges. In particular, fisheries conflicts arise when a marine resource is contested or disputed between a minimum of two actors. Despite the potentially large impacts of fisheries conflicts on marine-based economies, it is difficult to quantify the impact of conflict on fisheries production or on long-standing cooperative relationships that can be vital to the long-term sustainability of a given fishery. Previous work addressing fisheries conflicts has had a limited focus on quantitative measurements of how changes in fishing effort can influence how communities fall into conflict or make concerted efforts to cooperate. To address this knowledge gap, instances of conflict and cooperation amongst fishers in Puerto Rico were documented and categorized into different intensity levels. A linear probability model was then developed to estimate the probability of a conflict event occurring in a specific region, month, and year from 2012 to 2017. The model includes catch per unit effort as a predictor variable and controls for environmental factors. We found that an increase in catch per trip from the previous month has a negative and significant relationship with the probability of a conflict event. This result provides quantitative evidence for the supply-induced scarcity hypothesis, highlighting the importance of managing fisheries sustainably, to avoid future fisheries conflicts.