2  Sound in the marine environment

Soundscapes: “ambient sound in terms of its spatial, temporal, and frequency attributes, and the types of sources contributing to the sound field”.

2.1 The nature of sound in the marine environment

2.2 The decibel scale

2.3 Sources of noise (Duarte et al. 2021)

• Shipping noise
• Pile driving
• Seismic airgun
• Military sonar
• Acoustic deterrents

2.4 Impacts of anthropogenic noise on marine life

• Behavioural change
• Displacement – ie animals leave an area (Tyack 2008)
• Masking of communication
• Hearing damage - permanent & temporary threshold shift (Mickle et al. 2019)
• Stress
• Strandings & death

Duarte, Carlos M., Lucille Chapuis, Shaun P. Collin, Daniel P. Costa, Reny P. Devassy, Victor M. Eguiluz, Christine Erbe, et al. 2021. “The Soundscape of the Anthropocene Ocean.” Science 371 (6529): 1–10. https://doi.org/10.1126/science.aba4658.

Mickle, Megan F., Christopher M. Harris, Oliver P. Love, and Dennis M. Higgs. 2019. “Behavioural and Morphological Changes in Fish Exposed to Ecologically Relevant Boat Noises.” Canadian Journal of Fisheries and Aquatic Sciences 76 (10): 1845–53. https://doi.org/10.1139/cjfas-2018-0258.

Tyack, Peter L. 2008. “Implications for Marine Mammals of Large-Scale Changes in the Marine Acoustic Environment.” Journal of Mammalogy 89 (3): 549–58. https://doi.org/10.1644/07-MAMM-S-307R.1.