Sound detection and production in the American lobster, Homarus americanus: Sensitivity range and behavioral implications

Abstract

Many crustaceans including spiny lobsters, some crabs, and a few shrimp are known to produce sounds for a variety of purposes. One brief report and several preliminary studies indicate that American lobsters also produce sounds, and may be capable of detecting acoustic signals. The focus of this study was to (1) quantify the frequency range over which lobsters are capable of detecting sounds and (2) characterize the sounds that lobsters produce. Twelve sexually immature and 11 mature lobsters were tested for their ability to detect frequencies in the range of 20–10<th>000 Hz. Immature lobsters of both sexes detected sounds in the range of 20–1000 Hz (>50%), while sexually mature lobsters exhibited two distinct peaks in their acoustic sensitivity (20–300 Hz and 1000–5000 Hz). Lobsters of both sexes produced a buzzing vibration when grasped but larger lobsters (120–149 mm in carapace length) vibrated most consistently (>35% of surveyed lobsters). The greater tendency for sound production in large lobsters may indicate a role in mating behavior. Currently, we are characterizing the acoustical properties of produced sounds and investigating the possibility that the American lobster may produce sounds for more than one purpose. [Work supported by University of New Hampshire Center for Marine Biology.]