A framework for passive acoustic localization and tracking using a wide-baseline array demonstrated with Rice's...

Area of Science:

• Marine biology
• Acoustic monitoring
• Bioacoustics

Background:

• Passive acoustic monitoring is crucial for marine mammal behavior studies.
• Time-difference-of-arrival (TDOA) localization with wide-baseline arrays faces challenges with multiple sound sources and sparse sensor placement.
• Accurate localization is vital for understanding marine mammal ecology and conservation.

Purpose of the Study:

• To develop and validate a novel "track-before-detect" passive acoustic localization and tracking framework.
• To address the call association problem in TDOA localization using a hard-association approach.
• To characterize the behavior of Rice's whales (Balaenoptera ricei) using acoustic data.

Main Methods:

• Implemented a "track-before-detect" framework operating in the TDOA domain.
• Utilized a hard-association approach to manage complex acoustic scenarios.
• Applied the framework to low-frequency vocalizations of Rice's whales recorded offshore of Northwest Florida.

Main Results:

• Successfully extracted 398 Rice's whale tracks between May and August 2021.
• Estimated a median inter-call interval of 5.8 minutes for Rice's whales.
• Analyzed 1731 hours of data, revealing whales primarily swim parallel to the continental shelf break at an average speed of 0.9 m/s.

Conclusions:

• The developed passive acoustic framework effectively overcomes TDOA localization challenges.
• Quantitative behavioral parameters for Rice's whales were successfully estimated.
• The study highlights the framework's utility for marine mammal behavioral research and conservation efforts.