Buzzing sounds used as a mean of intra-specific interaction during agonistic encounters in male European lobsters (Homarus gammarus)?
Résumé
Passive acoustics is a useful non-invasive tool to collect behavioral information in marine species. This is the case for temperate crustaceans which are known to emit a large variety of sounds through diverse mechanisms. But despite numerous studies in tanks, little is known about their ecological meaning, particularly for decapods of high commercial interest. When stressed by handling, the European lobster (Homarus gammarus) vibrates its carapace and produces low frequency “buzzing sounds” that can be characterized in tanks. In this presentation, we discuss a straightforward experimental approach to investigating the role of these buzzing sounds in male European lobsters by combining passive acoustics and behavioral analysis (video and accelerometry). We recorded sound and video simultaneously during agonistic encounters. Based on the video, an ethogram was created with a total of 30 behaviors regrouped by agonistic levels. During agonistic encounters, European lobsters emitted buzzing sounds in association with stressful events such as claw grasping or tail flipping. Our results suggest that these sounds may be used by H. gammarus to maintain dominance around its shelter.