Acoustic Response and Detection of Marine Mammals Using an Advanced Digital Acoustic Recording Tag
RC-1188
Objective
A Ziphius cavirostris in the Canary Islands.
Environmental compliance requirements regarding the potential impacts of noise on marine mammal populations creates a need to develop methods for assessing those impacts. Determining how marine mammals use and react to sound is of particular concern to the Department of Defense (DoD), because these animals have been reported to mass strand during naval exercises where sonar is used. Such determinations have proven challenging, as not knowing safe exposure levels to sonar for deep diving whales hinders assessments of the potential impact of Navy active acoustic operations on marine mammal behavior and prevents accurately estimating the potential number of “takes” resulting from such operations.
The objectives of this project were to (1) determine the feasibility of monitoring marine mammals in select Navy undersea ranges; (2) assess the availability, variability, and probability of detection and classification of the marine mammals; and (3) develop methods to determine the near- and long-term effects of Naval active acoustics on marine mammals in their natural ocean environment in select ocean areas of Navy interest.
Technical Approach
Photo-identification showing repeated sightings of the same individual Cuvier’s beaked whales, Ziphius cavirostris, on different days (upper row and lower row) in the Ligurian Sea.
A digital acoustic recording tag (DTAG) has been developed to measure the received level of stimulus at a whale while also measuring behavioral and physiological responses. The tag tracks responses of marine mammals (especially deep divers) throughout their dives. This information provides an improved understanding of the functions and costs of behaviors to infer the biological significance of behavioral disruption. Methods for attaching these tags have been tested on deep-diving beaked whales to prepare for studies of how they respond to carefully controlled exposures of man-made noise. Whales at multiple sites were tagged to estimate the probability of range sensors detecting their vocalizations.
Results
Under SERDP Project RC-1539, follow-on research is under way to (1) ground truth acoustic monitoring on Navy ranges using boat-based observations and DTAGs; (2) develop tagging techniques and field efforts that use the DTAG to observe and monitor reactions of marine mammals to exposures of anthropogenic noise; (3) explore potential controlled exposure and opportunistic observation methods to evaluate safety zones based on beaked whale responses to sound; and (4) prepare a detailed plan for a research program to study the effects of multiple stimuli including experimental controls.
Benefits
Data on behavioral reactions of deep-diving whales and other cetaceans to Navy noises make it possible to estimate the impact of naval operations on sea life. Vocalizations recorded point to a great potential for implementing passive acoustic detection of these species in important Navy undersea ranges and for developing monitoring and mitigation tools. (Project Completed - 2007)
Project Documents
Symposium & Workshop
FY 2013 New Start Project Selections
Points of Contact
Principal Investigator
Dr. Peter Tyack
Woods Hole Oceanographic Institution
Phone: 508-289-2818
Fax: 508-457-2041
Program Manager
Resource Conservation and Climate Change
SERDP and ESTCP
Project Documents
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.