Natural darkness has a conservation value in the same way that clean water, air and soil has intrinsic value. Artificial light at night is increasing globally by about two per cent per year (Kyba et al., 2017). Over the 25-year period 1992 – 2017 artificial light emissions increased by at least 49% (Sánchez de Miguel et al., 2021). Animals perceive light differently from humans and artificial light can disrupt critical behaviour and cause physiological changes in wildlife (Russart and Nelson, 2018; Sanders et al., 2021). For example, hatchling marine turtles may not be able to find the ocean