The School of Marine Sciences presents
Dr. Phillip Lobel
Boston University
Scuba divers are usually oblivious to the soundscape of underwater noises. Exhaled bubbles and boat noise can often mask our being able to hear sonic fishes and “choral” reefs. For these reasons, underwater acoustic ecology has been largely overlooked until recently. Advanced diving technologies such as closed-circuit Rebreathers allow divers to increase their awareness of the natural structure and tempo of the ambient acoustic world underwater. More importantly, the underwater soundscape is becoming a focus for research on fish bioacoustics with an application to fisheries processes especially spawning cycles. The modes of reproduction among fishes range from having defined nests of benthic embryos to the random release of gametes in the water column where the embryos float and disperse in ocean currents. The spectacular annual mass spawning behavior of snappers and groupers is hypothesized to occur at locations where the underwater topography creates special flow conditions resulting in the favorable advection of embryos. The spawning behavior and sounds made by a variety of coral reef fishes will be reviewed using audio-video recordings of the Central Pacific (Johnston Atoll), Western Pacific (Palau, Tahiti, Pohnpei), Eastern Pacific (Mexico), the Caribbean (Jamaica, Belize) and cichlids in a freshwater lake (Malawi).
The key method in defining the locations of spawning sites is the direct observation by scientists of where, when and how different fishes engage in the reproduction ritual. This requires skilled scientific diving (preferably with Rebreathers) and documentation by stealthy photography/videography. The first scientific challenge is knowing where and when to dive. The second challenge is to gather sufficient data, especially video, to define a species’ reproductive behavior. This seminar will show where, when and how a variety of coral reef fishes spawn
Polycom availability with Darling Marine Center, Gulf of Maine Research Institute, and Bigelow Laboratories
Host: Mark Wells