Behavior and Sound Production by Longspine Squirrelfish Holocentrus rufus During Playback of Predator and Conspecific Sounds

Luczkovich, Joseph J. and Keusenkothen, Mark (2007) Behavior and Sound Production by Longspine Squirrelfish Holocentrus rufus During Playback of Predator and Conspecific Sounds. [Other peer-reviewed publication]

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    Fishes and marine mammals make sounds and listen for predators and conspecifics, i.e., they communicate underwater using sound. Longspine squirrelfish Holocentrus rufus are nocturnal reef fishes living in the Caribbean that commonly produce low-frequency sounds at dawn and dusk. In order to determine the reactions of longspine squirrelfish to sounds made by their conspecifics and by their potential predators, we performed experiments in which we played the grunting sounds of longspine squirrelfish and the echolocation and signature whistle sounds of bottlenose dolphin Tursiops truncatus through an underwater speaker on the reef at the Institute for Marine Studies, Calabash Caye, Turneffe Atoll, Belize. At the surface, a portable laptop computer was programmed to playback a series of sounds in the following sequence: pre-playback period with no sounds (8 min in experiment 1, 5 min in experiment 2), 700-Hz tone (10 min), longspine squirrelfish grunts (10 min), bottlenose dolphin echolocations (2 min), bottlenose dolphin signature whistle (2 min), and a post-playback without sounds (1 min in experiment 1, 2 min in experiment 2). Both the squirrelfish and dolphin sounds were recorded in the coral reef areas surrounding the study site. We also played a 700 Hz tone as a control. We monitored the sound production from free-ranging longspine squirrelfish in the area near the speakers where we played the sounds, and recorded behavioral responses of the fish using a digital video camera in an underwater housing with integrated hydrophone. To minimize acoustic disturbance, we used closed-circuit rebreathers (Inspiration) during the experimental playbacks. We compared the amount of time the squirrelfish stayed in view, how long the fish performed visual displays (fin erections), and how often they vocalized during each of the playback treatments. We found that the amount of time longspine squirrelfish remained in view did not significantly differ among treatments. Likewise, the duration of visual displays did not significantly differ among treatments. However, the fish appeared to perform fewer vocalizations during the playback of bottlenose dolphin sounds relative to vocalizations made during other playbacks. Longspine squirrelfish may be listening for the hunting sounds made by predators and responding to those sounds by performing fewer vocalizations.

    Item Type: Other peer-reviewed publication
    Related URLs:
      Publisher: American Academy of Underwater Sciences
      Subjects: (A) Biodiversity > (AC) Fish > (ACB) Marine
      (H) Protected Areas > (HD) Marine Reserve
      Publication Sources: (3) Other Source > (3B) NGOs
      Date Deposited: 31 Jul 2014 04:47
      Last Modified: 31 Jul 2014 04:47

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