Data from: Artificial light at night alters trophic interactions of intertidal invertebrates

Despite being globally widespread in coastal regions, the impacts of light
pollution on intertidal ecosystems has received little attention.
Intertidal species exhibit many night-time-dependent ecological
strategies, including feeding, reproduction, orientation and predator
avoidance, which are likely negatively affected by shifting light regimes,
as has been observed in terrestrial and aquatic taxa. Coastal lighting may
shape intertidal communities through its influence on the nocturnal
foraging activity of dogwhelks (Nucella lapillus), a widespread predatory
mollusc that structures biodiversity in temperate rocky shores. In the
laboratory, we investigated whether the basal and foraging activity of
this predator was affected by exposure to night-time lighting both in the
presence and absence of olfactory predator cues (Carcinus maenas, common
shore crab). Assessments of dogwhelks’ behavioural responses to night-time
white LED lighting were performed on individuals that had been acclimated
to night-time white LED lighting conditions for 16 days and individuals
that had not previously been exposed to artificial light at night.
Dogwhelks acclimated to night-time lighting exhibited natural
refuge-seeking behaviour less often compared to control animals, but were
more likely to respond to and handle prey irrespective of whether
olfactory predator cues were present. These responses suggest night-time
lighting likely increased the energetic demand of dogwhelks through
stress, encouraging foraging whenever food was available, regardless of
potential danger. Contrastingly, whelks not acclimated under night-time
lighting were more likely to respond to the presence of prey under
artificial light at night when olfactory predator cues were present,
indicating an opportunistic shift towards the use of visual instead of
olfactory cues in risk evaluation. These results demonstrate that
artificial night-time lighting influences the behaviour of intertidal
fauna such that the balance of interspecific interactions involved in
community structuring may be affected.