Aquaculture - Acoustic Deterrent Device (ADD) use: parliamentary report

Glossary

Acoustic Deterrent Device - Non-lethal management measures that work by introducing noise.

Auditory weighting function - Transforms sound measurements, taking into account the frequency-dependent aspects of auditory sensitivity.

dB - Decibels

dB re 1 μPa @ 1 m - Unit for SPL, decibels at reference pressure of 1 micro Pascal, usually referred from measurements back to 1 meter from the sound source.

dB re 1 µPa²s - Unit for SEL, the integral over time for squared sound pressure.

CEE - Controlled Exposure Experiment

Fundamental frequency - The lowest frequency for a given sound.

Good Environmental Status (GES) - Seas which are clean, healthy and productive within their intrinsic conditions, and the use of the marine environment is at a level that is sustainable, thus safeguarding the potential for uses and activities by current and future generations.

HF - High Frequency

Hz / kHz - Hertz / kiloHertz

LF - Low Frequency

Pa / µP - Pascals / microPascals

PAM - Passive Acoustic Monitoring

Predictive habitat modelling - The use of computer algorithms to predict the distribution of a species across geographic space and time, based on absence/presence and environmental data.

PTS - Permanent Threshold Shift

RL - Received Level

RMS - Root Mean Square

Sensation Level - A measure in decibels of the intensity of a sound that is above an individual's minimum hearing threshold.

SEL - Sound Exposure Level The metric assessed for the accumulation of sound exposure (usually measured over 24 hours), this takes into account the duration and the source level as well as the hearing sensitivity of marine mammal through auditory weighting.

SEL_SENS - Sound exposure sensation level; The SEL referenced to the test subject's hearing threshold, from Götz and Janik (2013).

Signal - In the context of the report, the artificial sounds produced by an ADD that have specific frequency content, pulse rate and rise time.

SL - Source Level

SPL - Sound Pressure Level

Startle response - An unconscious defensive response to sudden or threatening stimuli, such as sudden noise.

TAST - Targeted Acoustic Startle Technology

TTS - Temporary Threshold Shift

VHF - Very High Frequency