Public perceptions and (lack of) support for mitigation of artificial light at night in coastal cities

Artificial light at night (ALAN) is an expanding environmental pressure in urban areas, yet effective mitigation depends on public support. We investigated how residents of two Chilean coastal cities perceive ALAN, its impacts and potential mitigation measures. Respondents demonstrated asymmetric environmental literacy, recognising the societal benefits of lighting while showing limited awareness of its ecological consequences, particularly for coastal-marine ecosystems. Support for mitigation depended on preserving valued social benefits, with greater environmental literacy associated with stronger acceptance of mitigation measures. Findings suggest that perceptions of safety, aesthetic value and institutional responsibility shape policy acceptance, highlighting the need to balance nature conservation with societal objectives. Rather than viewing ALAN as a technical lighting issue, we frame it as a social-ecological governance challenge. We argue that successful ALAN mitigation will require integrating environmental education, participatory decision-making and collaborative governance to achieve lighting policies that are both publicly acceptable and ecologically effective.