What is passive acoustic monitoring and how does it work?

Passive acoustic monitoring (PAM) is the practice of listening to underwater sounds using hydrophones and recording systems. Unlike sonar, PAM does not transmit sound — it simply detects and records acoustic signals such as marine mammal calls, vessel traffic, and ambient ocean noise.

How is PAM different from active sonar?

The main difference is that PAM is non-invasive. It only listens, making it ideal for long-term environmental studies and regulatory compliance. Active sonar emits sound pulses and listens for echoes, which can disturb marine life.

What are the main applications of passive acoustic monitoring?

PAM is widely used for marine mammal monitoring, ocean noise analysis, offshore energy and construction projects, fisheries research, and environmental impact assessments. It provides continuous data for both scientific studies and industrial compliance.

Can PAM provide real-time monitoring?

Yes. Modern passive acoustic monitoring systems can stream real-time acoustic data to researchers and regulators, allowing immediate decisions in sensitive marine areas. Alternatively, devices can be deployed for long-term archival recording and retrieved later for analysis.

What are the limitations of PAM?

PAM cannot detect silent animals and may face challenges in noisy environments where vessel traffic or weather masks signals. Localization also requires hydrophone arrays rather than single units. Despite these limitations, PAM remains one of the most effective tools for non-invasive underwater monitoring.

Passive Acoustic Monitoring | PAM Equipment by Turbulent Research

Explore Our Passive Acoustic Monitoring Solutions

Passive Acoustic Monitoring (PAM) helps researchers, regulators, and marine industries monitor underwater environments without interference. At Turbulent Research, we specialize in passive acoustic monitoring solutions that bring precision and reliability to underwater acoustic monitoring. Our technology captures detailed ocean soundscapes using advanced digital hydrophones, hydrophone arrays, and rugged recording systems designed for challenging marine environments. Whether you're conducting marine mammal research or long-term noise assessments, our tools support accurate, real-time insights into underwater acoustics.

With decades of innovation in passive acoustics, we help researchers, scientists, and environmental teams monitor the ocean with confidence. Explore how our advanced PAM systems redefine performance in modern acoustic monitoring.

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What is Passive Acoustic Monitoring?

Passive Acoustic Monitoring (PAM) is the method of listening to underwater sound using hydrophones and recording systems. Unlike active sonar, PAM is completely non-invasive and ideal for long-term studies, regulatory compliance, and real-time decision-making in marine environments. PAM systems can detect a wide range of acoustic signatures — from marine mammal vocalizations to vessel traffic and seismic activity — providing critical data without disturbing the ecosystem. Modern PAM solutions, like those developed by Turbulent Research, offer high-resolution recording, long deployment life, and seamless integration with telemetry systems for remote access. These capabilities make PAM an essential tool for both scientific research and industrial environmental monitoring.

Why Passive Acoustic Monitoring Matters

PAM is an essential tool for understanding and protecting marine ecosystems. It enables:

Marine Mammal Monitoring

Detect and track vocalizations of whales, dolphins, and porpoises.

Ocean Noise Analysis

Evaluate the impact of shipping, construction, or seismic activity on underwater soundscapes.

Environmental Impact Assessments

Meet regulatory requirements for offshore wind, oil and gas, and port development.

Real-Time Data for Better Decisions

Access streaming or logged data to make informed calls in sensitive marine zones.

Our Technology

Turbulent Research offers rugged, reliable PAM systems designed for demanding offshore environments:

TR-PORPOISE

SINGLE CHANNEL UNDERWATER ACOUSTIC MONITORING.

TR-ORCA

UNDERWATER ACOUSTIC DATA ACQUISITION PRODUCT FAMILY

TR-BLUE

FLEXIBLE OEM SENSOR PROCESSING

TR-TRAC

EASY-TO-USE SOFTWARE

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Ready to Monitor Smarter?

Whether you’re managing marine mammal risk, studying ocean soundscapes, or preparing for a regulatory review — Turbulent Research has the tools and expertise to help.

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Passive Acoustic Monitoring

PROTECT MARINE LIFE. UNDERSTAND OCEAN SOUNDSCAPES.