Modern society has experienced a rapid decline in frequency of human interactions with nature – a shift that may undermine motivation and support needed to protect and restore ecosystems under threat. The Extinction of Experience (EoE) theory posits that people’s decreasing exposure to unmodified, natural settings (e.g., wilderness) can reduce their overall connection to the environment, along with their motivation to support and engage in acts of conservation. These consequences can become self-reinforcing: continued degradation of ecosystems further reduces opportunities for human-nature interactions. Using the Great Barrier Reef (GBR) as a useful case study and drawing on a survey of 2,208 residents living in GBR catchments, we explore how resident-reef interactions shape support for conservation action and pro-environmental behaviour. We also ask whether factors (e.g., moral obligation and place attachment) mediate this EoE dynamic in the GBR. Our case study provides new insights on factors that influence GBR residents’ support for environmental protection and their pro-environmental behaviours, as well as the pathways through which resident-reef relationships are developed and sustained. Such insights could inform targeted community engagement initiatives and policy interventions aimed at strengthening resident-reef relationships to support future conservation efforts in the GBR and elsewhere.