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Updated: Jul 3, 2026
08:07
Environmental DNA Sampling from Whale-Watching Vessels for Cetacean Monitoring
Published on: April 10, 2026
Low frequency vocalizations attributed to sei whales (Balaenoptera borealis).
Mark F Baumgartner1, Sofie M Van Parijs, Frederick W Wenzel
1Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543.
The Journal of the Acoustical Society of America
|August 7, 2008
Summary
Researchers identified low-frequency sei whale (Balaenoptera borealis) calls using acoustic recorders. These unique downsweep vocalizations were strongly associated with sei whale presence off Cape Cod, aiding in species identification.
Area of Science:
- Marine bioacoustics
- Cetacean communication
- Wildlife monitoring
Background:
- Low-frequency (<100 Hz) downsweep vocalizations were detected east of Cape Cod, MA.
- The species responsible for these calls remained unidentified.
Purpose of the Study:
- To identify the marine mammal species producing specific low-frequency downsweep vocalizations.
- To correlate acoustic recordings with visual observations of baleen whales.
Main Methods:
- Deployment of acoustic recorder arrays east of Cape Cod in 2006-2007.
- Collection of 70 hours of collocated visual observations.
- Comparison of call occurrence with right, humpback, and sei whale presence.
- Development of a synthetic kernel for automatic call detection.
Main Results:
- The low-frequency downsweep call was significantly associated only with sei whales (Balaenoptera borealis).
- Calls typically swept from 82 to 34 Hz over 1.4 seconds.
- Paired and triplet calls suggested potential production by a single animal.
- Automatic detection methods achieved 86% call detection with a 15% false positive rate.
Conclusions:
- The studied low-frequency downsweep vocalization is attributed to sei whales.
- Acoustic monitoring can aid in identifying and tracking sei whale populations.
- Automated detection systems show promise for bioacoustic research, despite limitations.
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