Ecological impacts of artificial nighttime light (Ecolight)

The global and regional distribution of artificial night-time lights has frequently been used as an indicator of the urban transformation of the land surface. However, more directly, such imagery also captures the spread of an evolutionarily unprecedented environmental change, the disruption across large areas of the Earth of the spatial and temporal (daily, seasonal, annual) patterns and cycles of light and dark that have previously remained approximately constant as a consequence of the Earth’s rotation, tilt of axis and orbital motion. This has raised ecological concerns, given that light and dark provide critical resources and environmental conditions for organisms and play key roles in their physiology, growth, behaviour and reproductive success, including providing cues used to entrain internal biological clocks to local time. Indeed, the potential has long been recognised that light pollution of the night may have profound consequences for the structure and functioning of populations, communities and ecosystems, and both science and policy documents regularly highlight this. Nonetheless, to date studies have focussed on obviously catastrophic effects on particular species, such as bird strikes on lighthouses and other tall lighted structures and the disorientation of hatchling sea turtles by beach-side lights. Empirical studies of the likely more pervasive and subtle effects on populations and communities remain wanting. We are working to bring about a step change in understanding of the population and community effects of night-time light pollution

[Key ref.: Bennie, J., Davies, T.W., Cruse, D., Inger, R. & Gaston, K.J. 2015. Cascading effects of artificial light at night: resource-mediated control of herbivores in a grassland ecosystem. Phil. Trans. R. Soc. B 370, 20140131; Bennie, J., Davies, T., Duffy, J., Inger, R. & Gaston, K.J. 2014. Contrasting trends in light pollution across Europe. Scientific Reports 4, 3789; Gaston, K.J., Bennie, J., Davies, T.W. & Hopkins, J. 2013. The ecological impacts of nighttime light pollution: a mechanistic appraisal. Biological Reviews 88, 912-27]