As humans, we rely on our sight more than any other sense. It’s how we navigate the world, identify individuals, and even catch our prey. But for killer whales and other cetaceans, who live in a murky underwater world with little to no visibility, sound is everything.
Around the world, though, whales are struggling to hear, and to be heard. Human-generated noise pollution is a major threat to the future of killer whales, most of which are endangered here in British Columbia.
How do killer whales use sound?
Killer whales use sound to communicate with each other, to locate food, to navigate in the lightless ocean depths, to keep social groups together, and to find potential mates. This is accomplished by using a variety of noises, including clicks, whistles, and pulsed calls.
All whales have different “languages,” and different species of whales can have different vocabularies. Transient killer whales, for example, sound much different and have different vocalization habits than resident killer whales.
Killer whales and other cetaceans have adapted to take advantage of the incredible physics of underwater sound.
Sound moves at a much faster speed in water than in air. The exact speed depends upon ocean temperature and pressure (depth), but generally speaking, sound travels about 4 or 5 times faster in water.
Sound travels a lot farther in water too. Under the right conditions, underwater sounds can travel thousands of kilometres across entire ocean basins. Low frequency calls, such as those emitted by blue whales, can travel especially far.
(Fact: Blue whales also produce the loudest sounds of any living creature! Their sounds are louder than a jet, which reaches only 140 decibels. For comparison, sounds over 120-130 decibels are painful to human ears. )
What are the causes of underwater noise pollution?
The ocean may seem peaceful and quiet, but it’s anything but. Over the past few decades in particular, the ocean has become a much noisier place. Explosions, military sonar, pile driving, seismic airgun surveys, marine construction, mining operations, and of course the ever-expanding shipping lanes all contribute to harmful underwater noise pollution.
How does noise pollution affect the whales?
All of this excessive background noise masks the call of other whales and interferes with their ability to locate prey. In other words, it interrupts their natural behaviours and makes it more difficult for the whales to thrive and survive.
How can I help?
By choosing a whale watching company that is not only committed to minimizing noise pollution, but that also makes the conservation of whales a top priority.
Here at Eagle Wing, we follow a strict set of guidelines that protects the overall health and long-term sustainability of whales in the Salish Sea. In addition, we operate an environmentally friendly fleet of whale watching boats that are designed to pose as little threat as possible to the whales and their habitat.
What’s more, we’re Canada’s first 100% carbon neutral whale watching company, and as a member of 1% for the Planet, we donate a minimum of 1% of all total sales to local environmental nonprofit projects. And that’s just the beginning! Check out all of our conservation initiatives.