Data from: Distracted decision-makers: ship noise and predation risk change shell choice in hermit crabs

Human induced rapid environmental change such as noise pollution alters
the ability of animals to integrate information cues. Many studies focus
on how noise impacts single sensory channels but in reality animals rely
on multi-modal sources of information. In this study, we investigated the
effect of anthropogenic noise and the visual presence of a predator on
tactile information gathering during gastropod shell assessment in the
European hermit crab Pagurus bernhardus. For hermit crabs, empty gastropod
shells are a crucial resource affecting growth, reproduction and survival.
We measured shell assessment behavior and manipulated (i) the shell size
(50% or 80% of the optimal), (ii) sound condition (ship or ambient) and
(iii) visual predator cue (absence/ presence). Overall we found that crabs
were less likely to accept an optimal shell in the presence of ship noise,
suggesting that exposure to ship noise disrupted the information gathering
ability of the crabs. We also found a significant interaction between
noise, predator presence and shell size on the mean duration for the final
decision to accept or reject the optimal shell. Hermit crabs in 50% shells
took less time for their final decision when exposed to both ship noise
and predator cue while crabs in 80% shells showed shorter decision time
only when the predator cue was absent. Our results indicate that
anthropogenic noise can interact with predation threat and resource
quality to change resource acquisition, suggesting that noise pollution
can disrupt behavior in a non-additive way, by disrupting information use
across multiple sensory channels.