Title: Potential effect of anthropogenic noise exposure on the exploratory- and cognitive-related behaviors of the Caribbean hermit crab (Coenobita clypeatus)
Abstract:
Recent studies have shown that anthropogenic noise pollution in coastlines has a negative impact on animals inhabiting these areas, potentially affecting their intraspecific communication, essential survival skills, physiology, and reproduction. This study investigates the effects of noise pollution that endangers the biodiversity within the littoral ecosystem, using the Caribbean hermit crab (Coenobita clypeatus) as the experimental model. To assess the effects of noise exposure on short-term memory, decision-making, and thigmotaxis (centerphobia), we used a behavioral test battery, including the novel object recognition (NOR), open field arena (OPA), and shell selection (SS) tests. Laboratory-habituated animals were divided into three groups: a control group (no exposure to anthropogenic noise), an acute group (exposed to noise during the test), and a chronic group (exposed to noise for 14 hours prior to the test). Animal behaviors were analyzed using the EthoVision XT program. We hypothesized that both acute and chronic exposure to anthropogenic noise would impair the animals' normal behavioral responses assessed through the test battery. Experimental results showed that chronic noise exposure statistically reduced the exploration behavior, as measured in the NOR test, compared to the acute or control groups (p < 0.05), without affecting the animal's short-term memory. The altered exploration behavior was accompanied by an increase in thigmotaxis in animals exposed to both acute and chronic noise in comparison to control animals, as demonstrated in the OPA test (p < 0.05). The SS test revealed distinct initial and final shell selection patterns depending on the experimental group. These findings suggest that prolonged exposure to noise pollution can alter the Coenobita clypeatus' concentration, increase indecisiveness, and modify exploration patterns. The impact of anthropogenic noise pollution highlights the need for awareness and noise regulation to protect their survival in natural environments.
