The impact of artificial light at night (ALAN) is currently recognized as one of the most widespread forms of human-induced environmental alteration. In coastal areas, the accelerated expansion of infrastructure and lighting networks has exposed nearly 22% of the world’s coasts to this stressor, generating significant impacts on the species that inhabit these ecosystems.
In this work, we evaluate the impact of artificial nocturnal light on the trophic behavior of the intertidal amphipod Ampithoe valida, with emphasis on sex-dependent responses. Under artificial night light, females significantly reduced their food consumption during the night, and their absorption efficiency was also lower, which could be a result of the stress generated by exposure or the alteration of their circadian rhythms. Males, on the other hand, increased their nocturnal food consumption under ALAN, evidencing the use of this new light-induced niche.
Ampithoe valida plays an important role in regulating macroalgal biomass in the intertidal, so alterations caused by artificial night light could generate cascading effects throughout the ecosystem. These effects could include changes in the abundance of macroalgae and in the availability of resources for other species and, consequently, a general alteration in the trophic dynamics of the intertidal.
Reference: Jahnsen-Guzmán, N., Quintanilla-Ahumada, D., Blum, R., Gadda, A. F., Amorin, O. A., Miranda-Benabarre, C., Pulgar, J., Duarte, C., & M. S. Valiñas. 2025. Impacts of Artificial Light at Night (ALAN) on coastal ecosystems: A study on the herbivore Ampithoe valida with focus on sex-dependent responses. Marine Pollution Bulletin: 117624. https://doi.org/10.1016/j.marpolbul.2025.117624.
Working in the intertidal of Playa Magagna (Chubut)