The nature, extent, and ecological implications of marine light pollution

© The Ecological Society of America www.frontiersinecology.org A light at night is globally widespread (Cinzano et al. 2001), rapidly expanding in spatial extent (Hölker et al. 2010), and shifting in its spectral characteristics (Davies et al. 2013a). Increasing concern over these trends has recently fuelled a surge in research toward understanding the ecological impacts of artificial light pollution (eg Davies et al. 2012, 2013a; Stone et al. 2012; Dominoni et al. 2013). While the impacts of light pollution are increasingly well documented in terrestrial ecosystems, marine habitats have received comparatively little attention (Depledge et al. 2010). Indeed, in a recent survey in which 592 coastal scientists were asked to prioritize global coastal research questions, artificial light was not included (Rudd and Lawton 2013). Yet, worldwide, more than a billion people (~23% of the global population) live within 100 km of a coastline (Small and Nicholls 2003), and many coastal marine ecosystems are exposed to artificial light at night. Here, we draw attention to artificial light as an environmental issue in marine systems, document its current spatial extent, and highlight a wide array of known and potential ecological impacts.