The unseen threat of noise in our oceans

Marine biologist Kristin Westdal discusses the unseen threat of nose in our oceans.

Video source: TEDx Talks / YouTube.

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KRISTIN WESTDAL: Thank you.

I love my job. I'm a marine biologist, and I work up in the Artctic alongside Inuit hunters and government biologists studying beluga, narwhals, killer whales and other marine mammals. But what I really want to talk to you about today is sound. Sound, and how it's affecting marine mammals in the north.

Now, one of the wonderful things about my job is that what I wear to work on a casual Friday is probably a lot different than what you wear to work. A typical day for me in the field is really anything but typical. Now, my drysuit is too big. Anyone who works in the Arctic in the water can tell you that having a drysuit that doesn't fit you is a really really bad thing. Every time I move I can feel a little bit of water running down my arms, running down my legs and pooling at my feet. I'm also standing about waist deep in freezing cold water, I'm bracing myself up against one of my colleagues, I've got pliers in one of my hands, I've got a glove in my mouth because if I put it down it's going to drift away, and I've got my other hand on the back of a beluga. I'm working to attach the wires of a satellite transmitter to the animal, as you can see in this photo behind me. We're trying to figure out where these animals migrate to, and what parts of their habitat are important for them in order to protect their critical habitat for the future. Now the whole thing from capture to release of the animal takes about 20 minutes, but I could certainly never tell you that. I have no idea what's going on around me, what other people are saying, what they're doing, other than what's right in front of me, which is this beautiful, glossy, rubbery-feeling animal that every now and then lets me know it's OK, because I can feel this kind of body against me, and I can also feel this kind of wet, fishy breath on the side of my face.

But I can certainly tell you that working around marine mammals, university certainly doesn't prepare you for capturing and handling whales. Now, these are photos of belugas. You've probably seen photos before, they're pretty magnificent animals. But what I want to share with you is what they sound like, what they sound like under water, to give you an idea of how critical noise is to these animals.

(Beluga sounds)

It's pretty amazing if you haven't heard it before. Now I get pretty close to these animals in their natural environment, but what I'm really curious about is sound, and how sound is affecting them and their natural behaviour. 

So here's the problem. If I told you that this year was the lowest extent of summer sea ice on record, you probably wouldn't be surprised. It's all over the news. But what might surprise you is how this is actually affecting these animals and their habitat right now, even before the ice disappears, which is actually another problem on its own. So as the sea ice changes, so does development. We have industrialisation in the Arctic. There's a lot of money at stake. We have commercial shipping, we have oil and gas exploration. Now we can all see what this might do to the marine environment, but I think it's what we can't see that is something that we need to think about right now. The noise all of this is causing in our environment might be doing more damage to the marine mammals than we could imagine.

(Icebreaker sound)

Now what you just heard was the sound of an icebreaker breaking ice through the surface of the water. It's quite loud. Now imagine if you added to that noise created by seismic surveys, noise created by drilling in the Arctic ocean. Now you have more noise created in the underwater environment, in the Artcic, created by humans, than we've ever had before. Now we're polluting our environment with more than just waste. We're polluting our environment with noise. Let me give you a sound example to put this in perspective. The people at the back of this auditorium can for surely hear me speaking, even if they're not clueing into what I'm saying. There's also probably people just outside the doors that can hear me speaking as well, if they have good hearing. But almost for sure there's no one out on the street, 100-200 metres away, doors or no doors, that can hear me speaking. Now, yes sound does travel differently in air than it does in water, but our human hearing, our undeveloped human hearing, is nothing compared to that of a beluga or a narwhal. These animals have the ability to communicate over tens of kilometres under water. Sound is also critical for their survival. They use sound to communicate between each other, they use sound to locate their food at depths, and they also use sound to locate their breathing holes.

Now recently the behaviour of these animals has begun to change. We've started seeing these animals avoiding commercial icebreakers at great distances. Beluga, for example, have been seen avoiding ships in distances of excess of 50 kilometres. So we know that this is affecting them. They want to keep a lot of space between these ships and themselves. But what we don't know is how badly this is affecting them.

What we do know, what ongoing research has suggested, is that all this noise is actually masking their ability to communicate properly with each other. 

This is a photo of an ice entrapment. It's a pretty gory photo, but I wanted to show you an example of what this looks like. So on the left we have a breathing hole that's left in the ice, and on the right we have a bunch of belugas fighting for the space to breathe. Ice entrapments in the Arctic are actually a natural occurrence. So they happen where winds pick up very quickly and water freezes over, and these animals don't have enough time to escape to open water. But recently we've been seeing this happening in places where it's never happened before, in places that predictably cover over with ice every year. Now in 2008, behaviour of these animals changed, and we saw over 1,000 whales perish in an ice entrapment—over 1,000 whales that were mainly mothers and calves. So try to imagine what that looks like. 1,000 whales. We're talking 3 to 5 metres in length, maybe a little less for the babies, and weighing up to the weight of a family van, all trying to breathe out of one hole. It's pretty disturbing when you think about it. And mothers and calves, it's obvious because the calves didn't have the lung capacity to make it out to the open water—which in this case was some 40 to 50 kilometres away—and the mothers weren't willing to leave their babies behind. In 2009, we had 30 to 100 animals die in West Greenland, and in 2010, 50 to 100 whales.

It just doesn't make a lot of sense. We have animals that predictably leave their summer grounds every year—end of September, beginning of October—that chose not to leave an area that completely covers in ice. Now imagine the panic, imagine the chaos, that would cause an animal to return to an area that wouldn't allow them to breathe.

What kind of noise were these animals hearing? How loud must it have been? What was different than before? Something had to have changed, right? So at the same time that these animals were beginning their migration—again, end of September, beginning of October—seismic activity was happening in North Baffin Bay. Seismic activity has never occurred in North Baffin Bay this late in the year, exactly at the time of migration. Scientists studying this problem suggest that this seismic activity caused an interruption in the traditional migration path of these animals and caused them to return to their summer grounds. Again, an area that completely covers in ice.

Now, loud noise confuses us all. That's for sure. Try to imagine that you're driving your car or riding your bike to work. And at the same time that you hear an ambulance siren, all the cars around you just lay on their horns. Now imagine trying to locate the ambulance noise amongst all the rest of the noise. Imagine trying to pick out that critical noise amongst all the rest and figure out where you should go. Another example: let's say that you're sitting in your office desk, and there's a pile driver operating outside of one window, and there's a truck moving forward and backward outside the other window, and your colleague is nattering away really loudly on the phone. Now imagine trying to have a critical conversation of your own. Or imagine trying to write a really important email. Pretty hard to focus, right? Now imagine if sound was how you located your food, or how you navigated.

A leading Danish researcher, Mads Peter Heide-Jørgensen, other colleagues, and I, believe that sound might be causing new and substantial problems. We think sound might be the reason for these fall ice entrapments of narwhal in new areas. 

Sound also travels over incredibly long distances under water. If you've ever been scuba diving, you've probably experienced this before: where maybe you hear a propeller noise and you look up, thinking it's going to be right above you because it sounds so close, and it's actually like way, way off in the distance. Seismic ship-based surveys, which are used to locate oil and gas deposits beneath the sea floor, create an incredible amount of noise. And this noise, which is created by explosions that generate sound waves, has been picked up over 3,000 kilometres from the ship source. Just try and imagine that. 3,000 kilometres! We're talking about farther than the distance from Vancouver to my hometown of Winnipeg. Imagine being able to pick up one noise in that distance. And, perhaps more importantly, the noise that's created by these surveys is actually operating at a frequency which overlaps that of narwhal communication. Imagine the confusion that these animals must be undergoing when a survey is happening. How do you think we, as humans, might compare in this situation?

Now what if seismic surveys are the reason for these entrapments? What if ice breaking and year-round shipping in the Arctic has the same effect? What if noise of this magnitude has the ability to mask communications between mother and calf, mask the ability of these animals to find food at ocean depths, or for these animals to find their breathing holes, which ultimately means their survival? What if their winter grounds, where these animals do most of their yearly feeding, is inaccessible to them due to noise displacement? What if their food moves as well? That's an entirely different problem. 

As biologists continue to try and solve this mystery and study this problem, I can tell you that these animals, beluga and narwhal, have already taught me so much. I know that we have to take an even closer look at all this noise, at all the noise that we're creating in our environment, and all the questions that it raises. But we don't actually need to show an answer in order to get attention. Mads Peter, other colleagues, and I have a paper coming out in the coming months on this exact topic. And we're pretty excited, because it's a question still—what if, what if—but it's a question we hope will garner more attention. Now, biologits and Inuit hunters agree that noise pollution in the Arctic is a concern. Seismic, ship-based sounds are a concern. Inuit hunters got an injunction on Baffin Island against seimsic testing in Lancaster Sound in 2010, an area that they're currently negotiating as a National Marine Conservation Area. These animals, part of an important subsistence harvest, were way too critical to them, and they didn't need absolute proof of negative impacts in order to stop it. It's so easy for us to focus on all these kind of big, in-your-face environmental issues. We're bombarded with these images every day. But I think that it's never been more clear that not all the damage that we're doing can be seen. And I think in order to solve this problem, to fix things going forward, we're going to need to close our eyes, and open our ears. Thank you.

Noise pollution and the environment

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