For whales, underwater noise is pollution too

Far from being the “silent world” of Jacques Cousteau’s famed documentary, the ocean actually abounds with natural sound. From the acoustic carapace vibrations of American lobster and small grunts from Atlantic cod to the high-frequency echolocation clicks of orca and deep vocalizations of enormous blue whales, the ocean sounds like a veritable symphony.

Humpback whale
© Shutterstock

Travelling five times faster in water than air, sound is the most effective means for marine life to communicate across the ocean’s vast expanse. But their musical notes are slowly sinking below a thickening layer of human-caused noise.

With the increasing industrialization of the ocean over the past several decades — port expansions, shipping intensification, oil and gas exploration and development — human caused noise is starting to overwhelm the natural ocean soundscape. And the impacts are now being documented across marine ecosystems, from whales down to plankton.

Underwater noise pollution has been linked to disrupting normal behaviors, masking communication, impairing feeding, and increasing stress levels; even causing permanent injury or death. Compounding existing stressors like overexploitation, chemical pollution and changing ocean conditions, in contributes to species decline and ecosystem degradation. Such losses are most immediately felt by Indigenous and other coastal communities who depend on marine resources for their wellbeing and livelihood.

How to quiet oceans for marine life

Bordering three oceans, Canada has a global responsibility to be a bold leader in underwater noise pollution prevention and to drive technological innovations that create environmental, economic, and social benefits. Recognizing this need, the federal government has started to develop an Ocean Noise Strategy that will guide and coordinate efforts at managing underwater noise over the next decade.

But to effectively reduce underwater noise pollution, a combination of management efforts with defined targets is required. Here are some of the priorities we’ve identified in our submission to the Canadian government as they build out their strategy. (To read our full commentary, click here):

Set thresholds based on biological limits and informed by Indigenous and local knowledge. If we try to minimize noise without considering both types of knowledge, we will not necessarily achieve what nature and people need.

Incentivize quieter technologies. Industry has a critical role to play in spurring the development and adoption of quieter technologies, and we can help nudge them along.

Develop vessel-based and area-based noise targets. While we must limit noise emissions from ships, different areas also need different approaches, such as quieting heavily trafficked habitats with endangered southern resident killer whales and beluga or preserving natural soundscapes in the rapidly developing Arctic.

Ensure strategies are implemented. Marine protection legislation very rarely includes shipping restrictions and never includes noise restrictions. Unless Canada’s Ocean Noise Strategy becomes legally binding via regulations or ministerial authority, we’re unlikely to see important biological areas actually free from noise pollution.

WWF-Canada will continue participating in the Ocean Noise Strategy process to ensure Canada creates the quiet spaces that allow the ocean’s natural rhythm to return.