Ocean swimming has been my greatest discovery of this coronavirus pandemic

I’d be lying if I said I wasn’t a little freaked out the first time I saw a shark on my swim out of Sydney’s Manly Beach. Time almost stood still as the sleek figure weaved below me. Disbelieving, I thought: “That looks like a shark.” No one around me in the water even blinked an eye, and the baby grey nurse drifted off into the deep blue.

I have been a swimmer all of my life, but the idea of a shark encounter had pretty much kept me out of anything beyond the surf. That was until the Covid-19 lockdown. I had been covering the pandemic for the Guardian since the virus first emerged in China in January. At times I had found myself overwhelmed by the story’s immensity and the grim reality of how it had taken over our lives.

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At night, my dreams were filled with the images of the pandemic I was reading and writing about during the day. I needed a circuit breaker. So when my friend Kirsten asked me to join her at Manly on Sydney’s northern beaches one day, I decided to give it a try.

We started in the warmth of March when all you needed was a cozzie, a cap and goggles. Those first few swims were mostly about survival, as I hadn’t been in any water for a while. But the natural break at 750m when you hit Shelly Beach was a good place to have a rest before the return leg.

Shelly Beach is reckoned to be the only west-facing beach on the entire east coast of Australia. Its headland protects the route from the southern end of Manly, which means the swim is almost always pretty calm. It’s also home to the Cabbage Tree Bay aquatic reserve, which is full of amazing fish, rays and the occasional (not-at-all dangerous) shark.

As the weeks turned colder, I wondered how long I would last. The water was bracing off the beach (especially at 7am), but with a little mind over body, I hoped I could keep going. As April turned to May, I invested in a wetsuit, determined to make sure I could get my daily coronavirus antidote in the ocean.

The swim has been filled with so many joys. Some talk of the benefits of cold-water therapy (to get the blood pumping) or how vitamin D might be a pandemic defence. But for me, getting into the ocean has been a reminder of what a tiny speck I am on this planet. The giant schools of fish, elusive rays, bright eastern blue gropers and cuttlefish in the bay have no knowledge or care about the pandemic. And for the half-hour of the swim, nor do I.

I have found myself using stored mental images from my swims to block the pandemic out of my brain. At night when I have worried about how or if the restrictions might end, or whether my dad may catch Covid-19, I have replaced those thoughts with the way the big cuttlefish in the bay, who some call Charlie, swims. I have often seen him alongside a groper, each of them about 80cm long. The groper focuses an eye on you as it passes. The cuttlefish will also lock eyes, but the way it swims is mesmerising. Its fins on the side of its body look like a cape that flaps in the water, as if in a breeze. It is the master of camouflage: sometimes green and brown, other times red. Docile wobbegong sharks “sleep” among the rocks. Huge rays bury all but their eyes in the sand.

It’s an amazing show of the ocean’s force and has been my greatest discovery of this pandemic. Each swim from Manly to Shelly is different. Close to the shoreline are weed-covered rocks and huge bare boulders. Swim a little further out and you cross the “drop off”, before hitting the sand dunes. The approach to Shelly is often filled with massive schools of fish. Some days the surf off the beach is huge and getting in is as challenging as getting out. Other days I have been lucky enough to body-surf to the sand. It has been exhilarating.

There’s a fascinating community that swims each day, many of whom are part of the Bold & Beautiful swim squad. Some have doled out much-needed advice: two caps keep your head warm in winter; fill an old two-litre milk bottle with hot water for a mini shower when you get out. And my most important tip for swimming through winter: try on your wetsuit before you buy it.