Broad spectrum artificial light at night increases the conspicuousness of camouflaged prey

The growing global prevalence of energy efficient broad spectrum lighting threatens to disrupt an array visually guided ecological processes. Broad likely better enables the discrimination colour, yet it is potential increase conspicuousness camouflaged prey at night remains little explored. Using a well-established visual model, we quantified impacts four spectrally distinct narrow and technologies on three different polymorphic colour variations intertidal littorinid snail, as viewed by model predators. Modern increased compared 20th-century lighting. This effect was most prominent in yellow morphs due greater contrast with their natural fucoid seaweed background. Synthesis applications. Our results provide evidence that transition will decrease efficacy camouflage nature, potentially altering selective predation, population dynamics genetic structure populations. These findings highlight need for further consideration environmental management planning, ensure habitats are protected from unnecessary exposure artificial light.