Details

Autor(en) / Beteiligte

• Yamamoto, Y.
• Yoshino, K.
• Koga, T.

Titel

Anti-predator responses to chemical, visual, and combined cues by an estuarine hermit crab from sandy tidal flats

Ist Teil von

• Behavioral ecology and sociobiology, 2023-06, Vol.77 (6), p.60, Article 60

Ort / Verlag

Berlin/Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2023

Quelle

SpringerNature Journals

Beschreibungen/Notizen

• Many aquatic invertebrates adjust their behavior to the degree of predation risk, which can be inferred from various sensory cues. We assessed the ability of the hermit crab Pagurus minutus to process different types of cues during predator avoidance and to discriminate between predators and non-predators by measuring the length of time that the hermit crabs remained retracted within their shells (hiding time) after exposure to visual cues, chemical cues, or both. Video images were used as visual cues, and water from aquaria holding predators or non-predators were used as chemical cues. The predator species was the portunid crab Charybdis japonica , and the non-predator species was the hermit crab Clibanarius infraspinatus. Natural seawater and background video were used as controls. Test individuals were exposed to each cue for 100 s. Both visual and chemical predator cues significantly increased hiding time in comparison to the controls, whereas non-predator cues did not significantly affect hiding time, indicating that P. minutus can discriminate between predators and non-predators from both visual and chemical cues. However, exposure to visual and chemical cues simultaneously did not significantly lengthen hiding times in comparison to exposure to a single cue type, indicating that there is no dominance in risk hierarchy between visual and chemical cues, and that P. minutus integrates information from both types of cues as if they were a single cue. We discuss the differences in our results from those previously obtained with a similar experimental design for the hermit crab P. granosimanus . Significance statement Animals must identify the most informative cues and integrate information from multiple cues to make the appropriate decisions for predator avoidance. When exposed to two types of cues, prey animals may assess them as a sign of multiple nearby predators even if the cues come from a single predator, leading to stronger response to two simultaneous cues than to either cue in isolation. It is still possible that prey animals integrate information from multiple cues as originating from a single predator. However, most studies have not fully considered this possibility. Our study revealed that P. minutus were able to discriminate between predators and non-predators from visual and chemical cues in isolation, but did not respond stronger to the simultaneous cues than to either cue in isolation. Our results suggest an example of non-additive response to multiple cues due to information redundancy among cue types.