Rising ocean temperatures and the melting of ice caps have resulted in a prolonged ‘open water’ season in the Arctic Ocean (McWhinnie et al., 2018). As a result, these ice-free waters have drawn further shipping and seismic activities in the Arctic Ocean, increasing marine vessel traffic levels. Such marine industrial development has transformed the Arctic Ocean from a quiet sanctuary to a man-made racket, posing an overwhelming threat to our whales (World Wildlife Fund, 2022).
Belonging to the taxonomic group called cetaceans, whales are recognised as highly vocal mammals that greatly depend on sound in crucial areas of their social and sensory biology (Tyack and Miller, 2002). Whales rely on clicks, songs, and whistles to look after their offspring and find food and mates (World Wildlife Fund, 2022). For instance, Beluga whales communicate with their own kind through whistles and produce clicks to echolocate, allowing them to navigate dimmer marine environments and locate food (Barry, 2020).
Whales receive and create sounds over a range of frequencies, with species such as the Bowhead whale producing low frequency sounds less than 1000 Hz and others such as Beluga whales producing high frequency sounds between a few thousand to 100,000 Hz (Stafford, 2013). However, many anthropogenic sources of noise coincide with the sound frequencies and amplitudes of those heard and produced by whales, disrupting their hearing abilities and communication patterns. For example, a study revealed that the cumulative noise levels from the firing of airguns for seismic exploration led to behavioural changes in Bowhead whales in the form of silencing (Katz, 2016).
Increased underwater noise levels can also trigger the abandonment of whale habitats. For example, Beluga whales tend to react negatively to ship traffic, vacating areas with passing ships (Halliday et al., 2019). Such behaviour does not only require them to expend additional energy but curbs them from engaging in essential activities such as basking and socialising (The Conversation, 2020).
The underwater noise problem is also further accentuated in the Arctic, with noise being amplified by the consistently low temperature of polar waters (Katz, 2016). As sound traverses larger distances and is nearer the Arctic water surface compared to temperate oceans, noise is being transmitted across the same depths that Arctic whales can be found (Katz, 2016).
So, what are some proposed solutions to protect these Arctic whales? Are they effective? Stay tuned and find out more in the next entry.
Until then, stay safe and stay woke! 🤔
References:
Halliday, W.D., Scharffenberg, K., MacPhee, S., Hilliard, R.C., Mouy, X., Whalen, D., Loseto, L.L. and Insley, S.J. (2019). Beluga vocalizations decrease in response to vessel traffic in the Mackenzie River estuary. Arctic, 72(4), 337-346.
Katz, C. (2016). Marine Mammals Unsettled as Arctic Noise Grows. Retrieved 22 February 2022, from https://deeply.thenewhumanitarian.org/arctic/articles/2016/02/19/marine-mammals-unsettled-as-arctic-noise-grows
McWhinnie, L. H., Halliday, W. D., Insley, S. J., Hilliard, C., & Canessa, R. R. (2018). Vessel traffic in the Canadian Arctic: Management solutions for minimizing impacts on whales in a changing northern region. Ocean & Coastal Management, 160, 1-17.
Stafford, K. (2013). Science Short: Arctic Noise. Retrieved 22 February 2022, from https://www.pewtrusts.org/en/research-and-analysis/fact-sheets/2013/06/07/science-short-arctic-noise
The Conversation. (2020). Beluga whistles and clicks could be silenced by an increasingly noisy Arctic Ocean. Retrieved 22 February 2022, from https://theconversation.com/beluga-whistles-and-clicks-could-be-silenced-by-an-increasingly-noisy-arctic-ocean-151065
Tyack, P. L., & Miller, E. H. (2002). Vocal anatomy, acoustic communication and echolocation. Marine mammal biology: An evolutionary approach, 59, 142-84.
Worldwildlife Fund. (2022). Growing underwater noise in the Arctic puts whales and other animals at risk. Retrieved 22 February 2022, from https://www.worldwildlife.org/pages/growing-underwater-noise-in-the-arctic-puts-whales-and-other-animals-at-risk#:~:text=Many%20marine%20animals%2C%20including%20narwhals,gas%20exploration%20in%20the%20Arctic.
Worldwildlife Fund. (2022). Protect Arctic whales from underwater noise. Retrieved 22 February 2022, from https://arcticwwf.org/action/noise/#:~:text=Whales%20use%20clicks%2C%20whistles%20and,can%20even%20damage%20their%20hearing.