Eliciting psychological and social constructs driving pro-environmental behaviour of Nigerian fish farmers: Evidence from a public goods experiment

Given the environmental risks associated with aquaculture, understanding the behavioural drivers behind fish farmers’ decision-making is critical for promoting sustainable practices. This study examines how fish farmers in Nigeria make decisions regarding environmentally sustainable practices. The study is based on a structured survey and an embedded environmental Public Goods Game (PGG) in which farmers made resource allocation decisions for themselves and as advisors in hypothetical situations where pollution from aquaculture negatively impacted both individual farms and the wider ecosystem. Data were collected from 126 randomly selected fish farmers. To interpret behavioural variation, the study applies a novel triadic framework that integrates Construal Level Theory, Social Value Orientation, and Cooperative Orientation and Collective Efficacy. The main findings are that 92% of the 126 fish farmers reported that they would adopt or recommend sustainable practices to others. Most farmers demonstrated consistency between personal and advisory decisions. This suggests internalized and stable normative commitments. The majority of fish farmers were classified as prosocial (i.e., showing concern for collective welfare), with smaller segments identified as strategic-cooperative, individualistic or ambivalent. A low Self–Other decision discrepancy, defined as the gap between choices made for oneself versus others, was significantly associated with prosocial orientation and higher collective efficacy, but not with cooperative orientation. Among demographic variables, only age was significantly related to advisory decision. These findings suggest practical implications including supporting cooperative structures that enable collective action and targeting interventions that strengthen farmers’ belief in group capacity (collective efficacy) to support environmentally responsible aquaculture.