Southern California Off-Shore RangE (SCORE)
|The Southern California Offshore Range (SCORE) is a region off the coast of California where naval operations are frequently conducted. It is also known to be abundant in marine mammals. The SCORE project was designed to determine the feasibility of acoustic monitoring for marine mammals within the Navy’s SCORE region. The research objective was to assess the detection and classification of marine mammals by acoustic methods, both continuous and ship based, in comparison with conventional ship based and aerial visual methods.|
| The SCORE project began in 2000 in collaboration with Cascadia Research Collective and NOAA Southwest Fisheries Science Center. This project was funded by the U.S Navy Strategic Environmental Research and Development Program (SERDP) and the Chief of Naval Operations- N45. The project was also supported by the Channel Islands National Marine Sanctuary.
Assessing the size of marine mammal populations has traditionally relied on visual surveys alone, but the addition of acoustic monitoring can complement these surveys if reliable protocols can be formulated and calibrated against visual techniques. Several fundamental issues must be resolved before acoustic monitoring can be reliably applied to marine mammal assessment. We conducted acoustic and visual surveys of marine mammals in the SCORE region to address the following questions:
1. What acoustic signals are produced seasonally by marine mammals in this region?
2. Can these signals be associated with particular marine mammal species?
3. Can these signals be detected and classified sufficiently well to allow tracking? Or
inversely, what density of acoustic sensors are required to monitor these animals?
4. How often do individual marine mammals vocalize and how variable is their
vocalization behavior? Is gender an important factor in determining vocalization
5. Can the number of animals in a given region be estimated from acoustic data? Can
acoustic estimates improve the abundance estimates derived strictly from visual
6. What behavioral information might be obtained from acoustic and visual monitoring?
7. Is it possible to relate animal activity to an event, such as a ship passage? The long
range goal is to analysis of what happens to animals following some naval activity.
8. Can acoustic monitoring be used to mitigate a potentially harmful event?
9. Can satellite and other environmental data (temperature, biomass/ocean color,
currents) provide a predictive habitat model correlating with animal presence and
Because the SCORE region is “on our doorstep” we were able to use the region not only to address the above questions, but also to test and use new instrumentation. Acoustic Recording Packages (ARPs) and the Bioacoustic Probe (BProbe) were first used in this region, providing many insights in the vocalization types, rates, and associated behaviors for several baleen whale species.
|Credit: Erin Oleson|