"Humans introduce considerable amounts of sound and noise into the oceans of the world," Krysl said. "Many marine organisms make acute use of sound for their primary sensory modality because light penetrates so poorly into water. The primary focus of our work is Cuvier's beaked whale because some have stranded and died in the presence of Navy sonar. The discoveries we made with regard to the mechanisms of hearing in the beaked whale also apply to the bottlenose dolphin and, we suspect, to all types of toothed whales and perhaps other marine mammals."
Krysl and his colleagues have been studying the effects sound has on marine life for the past nine years.
"This research program has a very strong experimental component, which has successfully generated digital models of the anatomy of a beaked whale, and has identified mechanical parameters of the biological tissues in the organs of a beaked whale," Krysl said. "We are continuing our current line of research on the beaked whale and conducting validation experiments with the bottlenose dolphin. We plan additional modeling refinements that will allow us to investigate the entire sound pathway from the sea water to the entrance to the cochlea. These projects address several primary objectives in the Navy's plan to understand demographics, acoustic exposure thresholds, and mitigation strategies for living marine resources."
The area of research that deals with noise in the ocean has indeed been growing rapidly with concerns over the rising levels of ocean noise resulting from shipping, petroleum exploration and production, and military exercises, Krysl said.
"We have recently seen that other researchers are adopting our methodology for analyzing the impact of sound on marine mammals, although we are currently the only group producing significant results," he said. "This project significantly advances
|Contact: Andrea Siedsma|
University of California - San Diego