Learning to listen: Engaging the Sunshine Coast community on underwater noise

We hosted a learning event on underwater noise.

There was a mix of anticipation and curiosity in the air as people filed into the Chapman Creek Hatchery Education building in Sechelt, BC on the unceded lands of the shíshálh Nation. This was the first in an engaging series of underwater noise workshops for the Sunshine Coast community, co-hosted by Raincoast, the Loon Foundation, and SLR Consulting. The workshops aimed to foster discussions and raise awareness about underwater noise pollution.

As I entered our “classroom” for the day and glanced at the salmon posters, life-cycle props, and whiteboard, I couldn’t help but realize that it had been a long time since I had participated in any form of in-person learning session in a traditional setting. This workshop was a welcome change from the virtual learning that most of us experienced during and since the COVID era. 

The strengths of learning in person

The room buzzed with palpable energy as everyone introduced themselves and chatted excitedly about their work, interests, and aspirations during this learning experience. There is a unique value in direct, face-to-face interaction compared to virtual communication. It allows people to connect on a deeper level and can help strengthen a sense of community and motivation. The U-shaped seating arrangement served to focus our attention and lively discussions throughout the day which is often lacking in online learning. 

Justin Eickmeirer (left) and Jonathan Vallarta (right) introducing the fundamentals of underwater noise to the class. Photo by Agathe Bernard.

We started our session with a round of introductions from a very diverse and passionate group of locals. Our first participant to introduce themselves was the Director of the Resource Management department for the shíshálh Nation. With over 40 years of experience working on the Sunshine Coast for his Nation, he proudly identified himself as an elder, which is something defined not by age but rather by the depth of cultural and traditional knowledge. His passion shone through as he shared his dedication to protecting the coast and learning more about the impacts on marine species, many of which are recognized as important cultural symbols.

As participants introduced themselves, each shared their own compelling story about what brought them there and their special connection to the ocean. The diversity in backgrounds and demographics was striking, with students as young as 11 years old,  First Nation elders, educators, conservationists, engineers, divers, film makers, business owners, long-time mariners, retired life-long learners, and many other concerned citizens. This broad assemblage of community members rallying around the cause demonstrated the significance and relevance of this topic to the whole community and not just those directly involved.

Our two instructors for the day were Jonathan Vallarta and Justin Eickmeier, underwater acoustic specialists from SLR Consulting. Collectively, they have over 30 years of experience working in underwater acoustics and both are passionate about sharing their knowledge with others.

Fundamentals of underwater sound

Jonathan started us off by introducing the basic principles and physics of underwater acoustics. These concepts can be intimidating, but each topic was broken into simple, bite-sized sections which kept everyone fully engaged.

He shared that sound is a form of energy made by vibrations that can only travel through a medium.  When an object vibrates, it causes the particles around it to collide with each other, which continues until they run out of energy. The result is a sound “wave” that travels, however individual particles simply oscillate back-and-forth in place.

To illustrate this concept, he conducted a live demonstration of the “Mexican wave” with the participants. If you’ve ever been in a packed stadium, you might have witnessed this or been a part of one. Starting at one end, successive groups of spectators rise and cheer, creating a wave-like motion that moves throughout the stadium, but each individual remains in one spot. 

Jonathan explaining how sound energy moves through a medium like a “Mexican wave”. Photo by Agathe Bernard.

Visualizing sound

Jonathan shared various methods used to measure and visualize sounds, such as different waveforms and colourful graphs. A particularly informative tool is the spectrogram, a visual representation of the spectrum of frequencies of a signal over time. In this representation,  the intensity of each frequency is represented by different colours. This allows for an appealing visual summary of soundscapes over time and lets one focus on particular periods or sounds of interest.  Jonathan pointed out that this is a welcome change to analyzing sound, compared to the days when people had to manually listen to recordings, a task that could take a lifetime! Understanding these fundamental principles of sound laid the foundation for further learning on what likely drew many to the session – to understand underwater noise and its impacts on marine species.

Example spectrogram of a humpback whale call. From Jasco Applied Sciences.

The ocean is a noisy place

The ocean is naturally a very noisy place, bursting with sounds long before human-generated noises were introduced. This includes environmental sources such as wind, rain, and crashing waves, as well as biological sources like invertebrates, fish, and whales. Surprisingly, Jonathan highlighted shrimp as being one of the loudest creatures in the ocean, capable of generating sounds that exceed 200 decibels, a sound louder than a fighter jet during takeoff! They sound like a string of firecrackers and the rapid closure of their snapping claws generates cavitation bubbles – akin to the explosive noise generated by the propeller cavitation of vessels. Our hearing senses heightened as Jonathan played audio clips of ice cracking, underwater earthquakes, toadfish and whales singing. The ocean soundscape is a captivating symphony of sounds. 

The problem of increasing anthropogenic noise

Unfortunately, there is one last category of noise negatively impacting the ocean soundscape: anthropogenic (i.e. human-generated) noise. This includes sources such as commercial vessels, oil and gas exploration, military sonar, and recreational boating. Commercial shipping has been identified as a primary source of noise pollution, given that over 80% of the world’s goods are transported via waterways, leaving few regions unaffected by shipping noise. Due to this, ambient noise levels have roughly doubled every decade since the 1960s.  Moreover, it is only expected to increase due to population growth, increased trade demands and the opening of new Arctic shipping routes amid melting sea ice. This global surge in underwater noise poses serious threats to marine organisms which rely on sound for survival and is recognized as a significant conservation concern.

Impacts of underwater noise on marine species

Earlier, we learned that in a deep, dark ocean, sound travels nearly 4.5 times faster in water than in air and can reach greater distances than light. In the right conditions for example, sounds emitted by blue whales can be heard up to 1,000 miles away.  Consequently, many marine species ranging from whales to larvae have evolved to use sound for essential life functions such as communicating, foraging, reproducing, and navigating.

One of the most pervasive ways noise can affect marine species is through auditory masking, whereby a loud sound drowns out a softer sound or when a noise occurs at the same frequency as a sound signal. This is particularly concerning as it can interfere with the reception of crucial acoustic signals necessary for species’ survival. For example, shipping vessels generate low frequency broadband noise that can strongly overlap with many baleen whale calls (like humpback and fin whales) and the frequencies used for echolocation by other marine mammals such as the endangered Southern Resident killer whales

Jonathan reinforced this concept by playing a recording of a Northern Resident killer whale attempting to vocalize amidst the noise of a passing ship. The clip begins with the energetic squeaks and squeals of a killer whale vocalizing, but is quickly drowned out by the loud and overbearing noise of a commercial vessel. As the sound of the approaching vessel dominates the soundscape, the faint efforts of this individual trying to communicate can still be discerned. The vocalizations soon become distorted and one can only imagine what the individual is trying to convey. This painful example highlights the ubiquitous and detrimental impact of noise pollution on marine creatures.

Increased noise pollution and auditory masking have been associated with increased energy use from marine mammals, altered behaviours (i.e. leaving important habitat or impaired anti-predator behaviour), auditory impairment, elevated stress levels, and even mortality. As expected, this topic sparked numerous questions and lively discussions among our participants. Many expressed concern about upcoming local projects that will increase underwater noise, emphasizing the importance of understanding the impacts not only to cetaceans, but to other local species such as crabs, salmon, herring, groundfish, prawns, and the rare glass sponge reefs found on the coast. 

Getting hands-on with hydrophones

After an engaging morning of classroom learning, it was time to stretch our legs and immerse ourselves in the sounds of the ocean firsthand with a specialized underwater microphone called a hydrophone. They are made from piezoelectric material that detects vibrations caused by pressure changes and converts them into  electrical signals. These signals can then be recorded and analyzed with computer software.

Photo: Jonathan highlighting the ocean soundscape through the spectrum (top) graph and spectrogram (bottom). Photo by Agathe Bernard.
Spectrum and spectrogram.
The Ocean Sonics software displaying a spectrum (top) and spectrogram (bottom) of the ocean soundscape in real time.

We headed to the pier at Davis Bay, where Jonathan walked us through how to connect our mobile devices to the hydrophone’s software. Immediately, the ocean soundscape came alive in our hands as we monitored the  hydrophone signals in real-time. Our screens displayed a spectrogram and a spectrum graph – another useful tool which denotes the power and frequency content of sound signals.

Justin shared that we were using an icListen smart hydrophone (Ocean Sonics): an impressive system that houses all the different monitoring components into one compact unit, streamlining the process of gathering acoustic recordings. The instructors highlighted how technology has advanced significantly, allowing us to effectively gather underwater noise data in two cases no larger than a lunchbox! Further, with the Ocean Sonics software, they can remotely monitor and analyze data in real-time from the comfort of their office. 

The acoustic monitoring system consisted of a control box (orange case), computer monitor and a hydrophone that was housed in a compact waterproof case (yellow case). Photo by Agathe Bernard.

As we observed our spectrograms, the instructors pointed out the bright green band spanning horizontally across the bottom of our screens.  They explained that this ever-present band we were seeing represented tonal sounds from vessels and nearby urban activities. In the distance, we could see a few ships passing by, undoubtedly contributing to this persistent ambient noise. 

They also highlighted the vertical strips of colour bands on our spectrograms, which represent broadband sounds spanning most of the frequency spectrum. These sounds typically stem from impulsive signals of shorter duration (less than one second) and higher peak sound pressure, often associated with activities such as pile driving, blasting, and seismic air guns.

Justin outlining the different components of the hydrophone system. Photo by Agathe Bernard.
The splash of three test rocks contributing to the ocean soundscape and animating our visualizations. Photo by Agathe Bernard.

Finding solutions to reduce vessel noise impacts

With the group now well-versed in underwater noise and equipped with hands-on experience, there was eagerness to learn more about how to tackle this issue. Justin walked us through various mitigation techniques, including innovative approaches such as the use of a bubble curtain. He highlighted an interesting example of ships using an air lubrication system (ALS) which creates a layer of microbubbles between the vessel’s hull and the water’s surface to reduce friction. This improves fuel efficiency, but also dampens the transmission of noise from the vessel’s internal machinery. This technique is inspired by nature, as humpbacks utilize bubble curtains to encircle and disorient their prey during feeding. 

Other mitigation measures were discussed, such as increasing the distance between vessels and marine life, retrofitting vessels with quieter propellers that reduce cavitation, and developing new technology for quieter ships. However, studies suggest that the most effective and straightforward way to reduce noise pollution at this time is to slow down ships. Fortunately, numerous initiatives such as the Port of Vancouver’s Enhancing Cetacean Habitat and Observation (ECHO) Program, are working towards implementing such measures. The ECHO program coordinates voluntary slowdown zones in known areas of importance, such as Haro Strait and Boundary Pass – both critical habitats for the endangered Southern Resident killer whales.

Unlike other sources of pollution that are more challenging to target and remove, such as airborne carbon dioxide or persistent organic pollutants, anthropogenic noise is a point-source pollutant whose effects diminish quickly once the source is removed. There’s still hope, but it is clear that definitive and immediate actions are necessary.

Key takeaways from our learning

There were some clear takeaways from our discussions,  providing direction for our next steps. 

1. Raise public awareness about underwater noise 

Underwater noise is a critical conservation priority and is being addressed by researchers, government agencies, and decision-makers. This awareness, however, also needs to extend to the broader public, as community efforts can contribute greatly to mitigation solutions. Workshops such as these are important to raise awareness and provide opportunities for citizens to create change through consumer demands, policies, and technological advances.

2. Empower local communities through training 

Jonathan shared an anecdote about a First Nations community that had recently been equipped with a hydrophone for monitoring the waters. However, lacking background information on underwater noise monitoring, they were left unsupported to operate the equipment and monitor effectively.  He stressed the importance of capacity building and empowering local communities to ensure effective monitoring efforts.  By receiving training and support, communities can work collectively: ensuring adherence to mitigation policies and guidelines in local regions, advancing research, and supporting a healthy marine environment.

3. Expand monitoring efforts

There is a need to monitor far and wide and as soon as possible to evaluate rising noise level impacts on marine species. With oceans quickly changing, and noise levels expected to increase continuously,  “baseline” studies to understand changing noise levels and their impacts on marine species are crucial. While the global decline in underwater noise levels during the COVID-19 pandemic provided a temporary quieter ocean for comparison, further data on true baseline noise levels is still needed.  

The Sunshine Coast is rich in acoustically active and sensitive species such as humpback whales and killer whales, however, acoustic monitoring in these waters remains sparse. With impending development projects set to increase noise levels in the region, it’s imperative to start monitoring here as soon as possible.

Fortunately, efforts are underway to address these gaps of knowledge. In 2024, Raincoast will launch a visual and acoustic monitoring station in the region, similar to our Raincoast whale sanctuary monitoring station on Pender Island. This station will offer an immersive window into the area and provide much-needed data on underwater noise. These data will help to inform region-specific mitigation efforts and support outreach and training. 

4. Strength in collaboration

It was immensely rewarding to have worked alongside individuals from SLR Consulting and the Loon Foundation to deliver such an impactful learning event for the community.  The success of this collaboration underscores the power of working together. Through our collective efforts, we shared knowledge, minimized costs, saved time, accelerated progress and successfully achieved our shared goals. We all look forward to future collaborations to contribute to monitoring and research efforts along the coast!  


Cross-border and collaborative efforts are essential when it comes to implementing effective mitigation strategies for underwater noise. Raincoast is spearheading the NoiseTracker initiative – a collaborative effort amongst hydrophone operators throughout the Pacific Northwest coast. This initiative will integrate acoustic data from existing operators into one centralized platform to provide much-needed trend data and facilitate evidence-based mitigation measures.

Informed and inspired

As the day concluded, our minds were brimming with a wealth of new information and ideas. Many expressed gratitude for the valuable experience and exchanged contacts, suggesting potential future collaborations to come. 

The workshop was a great opportunity to educate the public about the underwater soundscape and help foster stewards for the protection of acoustic habitats. We hope that the momentum generated from this event will continue to grow, spreading throughout the community, local governments, and beyond.

You can help

Raincoast’s in-house scientists, collaborating graduate students, postdoctoral fellows, and professors make us unique among conservation groups. We work with First Nations, academic institutions, government, and other NGOs to build support and inform decisions that protect aquatic and terrestrial ecosystems, and the wildlife that depend on them. We conduct ethically applied, process-oriented, and hypothesis-driven research that has immediate and relevant utility for conservation deliberations and the collective body of scientific knowledge.

We investigate to understand coastal species and processes. We inform by bringing science to decision-makers and communities. We inspire action to protect wildlife and wildlife habitats.

Coastal wolf with a salmon in its month.
Photo by Dene Rossouw.