Passive Acoustic Monitoring System

The noise from offshore activity has increased dramatically over the last decade. Man-made underwater noise has the capacity to directly cause disturbance to marine mammals, such as seals, whales, dolphins and porpoises, and may also cause secondary effects, for instance by disturbance of important food sources such as fish.

The effects of noise can include death or lethal injury, physical injuries that can have longer term consequences for the animal such as deafness, and sub-lethal behavioural effects such as the avoidance of an area. All of these may have significant consequences for individuals or stocks of a species.

Hence, it is generally a condition of consents issued for offshore activity that where the noise of an activity is sufficient to create an adverse effect, mitigation measures are introduced.

Generally, use is made of Marine Mammal Observers (MMOs) in an attempt to visually detect marine mammals, and delay operations until the animal has left the area. However, this approach can be ineffective and in darkness or poor visibility detection is impossible. Under these circumstances acoustic detection offers significant advantages.

Subacoustech has developed a Passive Acoustic Monitoring (PAM) system. This system uses sonar to monitor for vocalisations or echolocation signals from the animals. When they are detected the software displays the signal, the species detected and the distance from the monitoring vessel.

The system is capable of detecting marine mammals at distance, and estimating their location, with no left-right ambiguity. For any further information about Subacoustech's PAM system, please contact us to discuss your requirements.