SEA Science

Our Specific Areas of Focus

SEA is working in a variety of exciting scientific fields. Each of these quite different areas are related in terms of the overall objectives of SEA, namely to increase the understanding, management, and appreciation of marine and terrestrial ecosystems by working with scientists, industries, decision-makers, and the general public. Specific focus areas include: behavioral response studies, laboratory research on hearing and noise impacts; field research on pinniped vocal communication; noise exposure criteria and research recommendations; work with both conventional and alternative energy industries to understand and minimize environmental impacts of resource acquisition. Finally, Dr. Southall has been working extensively since 2004 with the commercial shipping industry on the issue of how shipping noise may be affecting the marine environment and technologies to possibly reduce it.

Behavioral Response Studies (BRS)

A current major research focus for SEA is studies of marine mammal communication and behavior and how each changes as a function of sound exposure. Using carefully-designed experimental protocols and advanced sensors to measure where animals are, their sounds and others in their environment, and their behavior before, during, and after controlled sound projections, we can safely measure how different individuals and species respond.

Dr. Southall has been a leading member and co-principal investigator of three recent pioneering behavioral response studies, focused mainly on effects of military sonar systems and deep-diving beaked whales. These efforts began in the Tongue of the Ocean, Bahamas with a large, interdisciplinary, international team of experts using an underwater, military listening range to conduct BRS-07. These efforts continued in the Bahamas in 2008 with BRS-08, and the combined results suggested that beaked whales there seemed to exhibit avoidance behavior of various sounds at levels well below those in other species. The BRS studies in the Bahamas were extended to focus on different beaked whale species in the Mediterranean Sea, MED-09, in areas outside military ranges; this project recently concluded and a blog detailing the project is available here. These various BRS efforts have been extended and integrated with other ongoing studies to focus on species other than beaked whales and, eventually, will use realistic sound sources in southern California. This BRS, SOCAL-10, is now underway.

The internationally-coordinated team of researchers who carried out the Behavioral Response Studies (BRS) in the Tongue of the Ocean, Bahamas in 2007 and 2008 recently presented six oral and poster presentations at the 18th Biennial Conference on the Biology of Marine Mammals in Quebec City, Canada. These included the combined scientific methodologies and accomplishments of BRS-07/08, as well as simultaneous biological and oceanographic measurements in the study area, detailed movement analysis of individual beaked whale responses, analyses of the vocal repertoires of tagged pilot whales prior to sound exposures, and results on vocal responses of pilot whales and other target cetacean species to controlled sound exposures.

Laboratory Research on Hearing and Noise Impacts

Dr. Southall has a long-standing partnership with the Pinniped Cognition and Sensory Systems Laboratory at Long Marine Laboratory, University of California, Santa Cruz (where he retains a research affiliation) for research on hearing and the effects of noise on hearing in seals and sea lions. These measurements have included basic hearing capabilities basic hearing capabilities, as well as controlled exposures to sound to measure how noise interferes with (“masks”) hearing and can cause temporary hearing loss in these animals.

Pinniped Vocal Communication

Dr. Southall and the Pinniped Cognition and Sensory Systems laboratory have also been collaborating for over a decade on studying northern elephant seals at Año Nuevo State Reserve. These studies involve measurements of sounds the animals make and natural background noise, as well as sound playback experiments.

Noise Exposure Criteria and Research Recommendations

While still with NOAAs Ocean Acoustics Program, Dr. Southall led two major efforts to synthesize data available on noise impacts for marine mammals and to make research recommendations to improve the science available to inform conservation management. These recent efforts, each of which involved interdisciplinary teams of colleagues, culminated in the publication of marine mammal noise exposure criteria and research recommendations, and a U.S. federal research strategy for the coming decade to understand and manage noise impacts on marine line. SEA, Inc. continues to work with decision-makers in government and industry in applying available science and identifying key studies to improve the knowledge base for better environmental decision-making.

Reducing Environmental Impacts of Offshore Energy

SEA, Inc. is working with a number of conventional and alternative energy companies on the acquisition and application of scientific data to better understand and minimize the environmental impact of resource acquisition. One example is that Dr. Southall serves as an external scientific advisor to the Joint Industry Program, which is a partnership of energy companies supporting research on the effects of oil and gas exploration and production. Ongoing research and consulting also involves offshore wind energy developments and various kinds of hydrokinetic power projects (including wave energy and tidal power).

Shipping Noise and Quieting Technologies

While military sonar systems and seismic airguns used in oil/gas exploration and scientific research have received considerable attention in the overall issue of noise impacts on marine life, less intense but far more widespread and chronically-present noise sources, particularly large commercial ships, have only recently begun to be specifically considered. While with NOAA, Dr. Southall organized and chaired the first international symposium bringing together scientists, industries, conservationists, and managers on this global issue (view the 2004 report). One recommendation of that meeting was to focus on technological possibilities and economic implications of quieting technologies for the largest vessels in the oceans; a follow-on meeting (also chaired by Dr. Southall) addressed just this issue (view the 2007 report). A related collaboration and focused symposium by Okeanos – Foundation for the Sea advanced these efforts, bringing in new partners and ideas (view the Hamburg report). These combined efforts lead to the development of an information paper presented by the United States to the International Maritime Organization (IMO) (see: MEPC 57-20) and subsequently to a proposal for a formal IMO correspondence group within the Marine Environment Protection Committee (see: MEPC 58-19). That proposal was accepted and the correspondence group is now working on specific recommendations for IMO regarding vessel quieting technologies (see: MEPC 59-19 for recent status). Dr. Southall continues to be an active participant in this process and in the issue of shipping noise internationally.