Laura Trethewey discusses her first book on the ever-changing composition of the ocean, and key threats the ecosystem faces

Toronto-born, San Diego-based Laura Trethewey describes herself as an ocean journalist. Her first book, The Imperilled Ocean: Human Stories from a Changing Sea (Goose Lane Editions), puts into perspective not only the ocean itself as a giant ecosystem, but also how we humans draw inspiration from and enjoy the seas, as well as how we fear, use and abuse them. “The ocean is dynamic, with many layers and angles,” Trethewey says. “My book is a cross-section sampling of what’s going on at sea and why that matters.” In short, the oceans can live without us, but we can’t live without the oceans. The Globe’s Susan Nerberg caught up with Trethewey as she was heading on a cross-Canada tour to promote her book.

Did you grow up by the ocean?

No, I’m from Toronto, but my family on my mother’s side is from the East Coast, so there’s a nautical background with sea lore and sailing. I loved hearing those stories and going there on vacations. Maybe because I didn’t grow up by the ocean, but it was a place I liked to visit, it made it more mysterious. One of my first memories is going to tide pools with my sisters and eating lots of weird seafood, like lobster and crab cakes. We were the kids who would pull things out of the ocean and ask if we could eat them.

You’re based in San Diego now. What’s your relationship with the ocean today?

The ocean has a calming effect that puts the world into perspective. My husband, who is a postdoctoral researcher at the Scripps Institution of Oceanography, and I made a conscious decision to make the ocean part of our daily lives. We go diving, fishing and tide pooling there, and I walk my dog on the beach.

How have you and your connection to the ocean changed as a result of writing this book?

The book turned me into a science journalist and environmental writer. Before it, I saw myself as a storyteller of the sea, not the ocean, with these romantic ideas about it. Then I saw the environmental urgency in every story; it wasn’t just in the background. Researching Chapter 2, about two hobby sailors crossing the ocean, I came across other sailors who had turned into environmentalists. And, when I talked with Syrian refugees, it may seem to many that it’s a humanitarian story that’s disconnected from the environment, but a contributing factor to the civil war was a historic drought that had led people to leave farms for the cities, which stoked civil unrest. That led people to cross the ocean, making the desperate choice to flee for asylum in Europe. So there was a huge change in me when I realized that there was this urgency to the situations in every chapter.

You call yourself an “ocean journalist.” What does that mean?

I like that term because I’m not only interested in the environment. I want to change the common misconception people have about the ocean, which is that it is separate from life on land. To be an ocean journalist means I can bring the ocean to the forefront and show how it’s wrapped up in every action we make on land.

People have always been drawn to the ocean, mostly to make a living. What was your motivation for going to sea to listen to its stories?

The sea was always a happy place for me, but not everybody was having that experience. Some people feared it; others were in awe of it. That was intriguing. There were the refugees in Chapter 3 and cruise-ship workers [in Chapter 6], who on the surface looked different but had a common, very human purpose: to find a better life on land. Environmental activists and scientists were looking for solutions to protect the ocean or find out more about it. The artists and sailors were driven by truth and beauty and freedom at sea. I was inspired by that, because I felt that even though our stories might seem very different, there was often this human desire at the face of it all. We are not as different [from one another] as we think. The ocean is an elemental place, and we have elemental reactions and needs to it.

The title is a reference to the environmental ills humanity is inflicting on the seas, and one of your essays takes us to the B.C. coast to clean up plastic pollution. What are the biggest threats to the ocean?

There’s a lot of debate as to where we should spend our resources and what is the most fundamental threat to combat today. There are three overlapping threats: overfishing, pollution and the changing composition of the ocean, resulting from ocean warming and acidification. They’re all making the ocean less and less functional. There are so many humans on Earth we’ve managed to have such an impact on the ocean, which is giant. We need to look at big, collective actions. Individual actions do count – researching and writing on plastics had a huge impact on how I use single-use plastics every day – but we need a larger systemic change. For that to happen, people have to start making big sacrifices, but we’re not seeing that level of commitment yet. The scope of what we’re facing is so large, it’s overwhelming, even paralyzing, for people. Telling humans stories that people can recognize themselves in is more powerful that trying to scare them into change.

Why does the ocean matter, and why should it matter to people who are landlocked?

If you live in a place where you don’t get to see the ocean every day, it can be a foreign place. Even if you live by the ocean, you still may not see what’s going on far from land. But the weather is made by the ocean. Every second breath is oxygen coming from the ocean. The vast majority of your internet runs on fibre-optic cables laid on the bottom of the ocean. Most of the objects in our homes are shipped by ocean before they come into our lives. Even though we don’t see the ocean day to day, there are invisible ways in which we are connected to and rely on it. There are things that happen out there that cannot happen on land, and it’s such a huge ecosystem that provides so many benefits. The book is trying to bring that into focus, especially for people who live far from the ocean.

Why talk to scientist Erin Stoddard and his tracking sturgeon on the Fraser River in B.C.; this seems more like an inland story.

The sturgeon has been around for millions of years and its anatomy has barely changed. But there is a lot of development pressure on the sturgeon. It moves between fresh and salt water, making it a good candidate for highlighting the connection between the two ecosystems and how we’re treating them. A lot of animals in the ocean move long distances – bluefin tuna migrate across huge areas, swimming in and out of different jurisdictions – and they suffer the most because they’re in places where we can’t always protect them. The sturgeon is a good example for looking at those issues – it goes from river to ocean and might be crossing the Canada-U.S. border, and it’s not doing very well. It’s not the big ocean creature people might expect, but it represents the many challenges of other ocean animals and their disappearing voices.

Five more books that will expand your horizon on the oceans

Vanishing Fish: Shifting Baselines and the Future of Global Fisheries, by Daniel Pauly, looks at how overfishing and political inaction on regulation is leading to a collapse of the world’s fish populations.

Sea Sick: The Global Ocean in Crisis, by Alanna Mitchell, examines how human-caused ocean acidification and deoxygenation are altering everything we know about the seas and what that means for creatures from plankton to blue whales.

The Outlaw Ocean: Journeys Across the Last Untamed Frontier, by Ian Urbina, explains how everyone from human traffickers to vigilante environmentalists exploit the oceanic hinterlands for bad and for good.

The Sea Around Us, by Rachel Carson, has the author most famous for the environmental classic Silent Spring talking about how she found her voice blending scientific facts with poetic flair.

Soundings, by Hali Felt, is the tale of how one woman’s mapping of the ocean floor in the 1950s changed oceanography and our understanding of the planet.

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