(Reuters) - This series has explored the damaging effects of warming waters in the world’s oceans on marine life – and human life. Stressed by this climate change hidden beneath the waves, fish and other marine species are facing enormous disruption.

What can you do to try to lighten your effect on these animals? We talked to five people intimately involved with the sea: a Norwegian seafood chef with a locavore emphasis; an explorer fighting to ban fishing in two-thirds of the world’s oceans; an environmental scientist concerned about the global boom in aquaculture; an entrepreneur training unemployed young people as “sea rangers” to protect marine reserves; and a New England sushi chef who focuses on invasive species.

CHRISTOPHER HAATUFT, CHEF

Slapping a 13-pound halibut as long his arm on his restaurant counter, Christopher Haatuft slips the tip of his knife in near the gills, then runs the blade tailward to slice off a fillet.

The snow-white flesh and its delicate texture are a favorite among customers at his Lysverket restaurant in the Norwegian port of Bergen, where Haatuft and fellow “Neo-Nordic” chefs are reimagining Scandinavian cuisine.

But Haatuft isn’t merely concerned with the flavor. He also knows exactly where the halibut was raised: the Glitne farm on a fjord north of the city, which uses land-based tanks to avoid discharging fish waste into the sea.

“I like using it because it’s a progressive way of farming fish,” said Haatuft, whose arms are emblazoned with tattoos dating to younger days in the punk rock scene. “I think chefs are starting to get very conscious about where the fish is coming from, and they want to make sure they represent the restaurant well by having sustainable fish.”

His latest goal is to persuade langoustine fishermen to sell him the octopuses that stray into their traps instead of killing them and throwing them back.

“I would love to see the fishing industry at least branch out from the industrialization that’s been going on into more artisanal, boutique types of suppliers,” Haatuft said. “There’s no doubt in my mind that five to 10 years from now, you’ll have more specialized wholesale fish suppliers that don’t necessarily do mass market, but they do line-caught, very easily traceable fish.”

ENRIC SALA, MARINE ECOLOGIST

Enric Sala is fighting for one of the most ambitious goals in the history of conservation: to turn almost two-thirds of the oceans into a marine reserve.

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Sound like wishful thinking? Sala and his team, working with partners around the world, have persuaded governments to create 19 protected areas in the decade since they launched the Pristine Seas project, which the National Geographic Society calls its largest initiative dedicated to environmental preservation. Added together, these new parks cover waters equivalent to half the size of Canada.

Sala believes that the quickest way to begin to buffer the oceans against the effects of climate change would be by banning fishing on the high seas — the maritime no man’s land not under any country’s jurisdiction that covers almost half the surface of the Earth.

“We are in a planetary emergency: Global warming and acidification are going to damage ocean life in a way that we have never seen before,” said Sala, a former professor at the Scripps Institution of Oceanography. “The science is clear, the economics are clear: Protecting the high seas could be the lowest hanging fruit for ocean conservation.”

“It’s easy to be depressed, but we should be enraged,” he said. “We need to redirect this anger, this energy, into positive action.”

JENNIFER JACQUET, ENVIRONMENTAL SCIENTIST

Majestic orcas, playful dolphins and gimlet-eyed great whites: These creatures have all cast their spell on generations of ocean lovers.

The cockles, mussels and clams feeding unobtrusively on the seabed don’t tend to ignite quite so much excitement. Jennifer Jacquet believes it’s time they did.

Jacquet, an assistant professor in the Department of Environmental Studies at New York University, believes that bivalves could hold the key to reducing pressure on ocean life under siege from fast-accelerating climate change.

Her logic is simple: A global boom in the aquaculture industry is placing an unsustainable burden on the oceans by using vast quantities of wild-caught fish to feed salmon and other farmed carnivores. If the industry switched away from farming carnivorous fish and produced low-impact shellfish and seaweed instead, it would do a lot to ease the pressure, she argues.

“Our argument is that we need to farm lower on the food web,” Jacquet said. “We need to rethink what aquaculture is and will be in the future. Otherwise, it will remain part of the problem – and the worst part is, people think it’s part of the solution.”

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WIETSE VAN DER WERF, ENTREPRENEUR

It’s one of the big wins for environmentalists of the past decade: Governments in many parts of the world have created new marine reserves to protect ocean life. But Wietse van der Werf, who spent years campaigning against illegal fishing in the Mediterranean and North Africa, fears these victories will amount to little if no one is there to keep out the poachers.

A Dutch environmental-activist-turned social-entrepreneur, Van der Werf believes he’s found a solution: hire veterans from the navy and marines to train unemployed young people as “sea rangers” to patrol areas that governments don’t have the resources to cover.

“The danger is that the legacy that we leave behind as a conservation movement is merely one on paper and it doesn’t actually mean anything,” Van der Werf said. “The question is: How are you going to monitor these areas?”

With backers including a foundation set up by former Google exec Eric Schmidt, his Sea Ranger Service works like this: Young people struggling with long-term unemployment apply for free training as maritime professionals. Applicants attend a five-week “boot camp” where one in four is selected to undergo months of training at sea. Once qualified, the crews then, for a fee, perform a wide range of tasks for government agencies, companies and research institutes.

The first team of 12 Sea Rangers is preparing to set sail next month in the North Sea.

“The maritime domain is changing very fast,” Van der Werf said. “If we’re talking about growing food offshore, if we’re talking about the energy transition, there’s a lot of work to be done.”

BUN LAI, CHEF

Chef Bun Lai had just cooked a meal of fried inch-long silverside fish and tiny invasive Asian shore crabs along with tempura wakame seaweed – all of which he had harvested from the nearby Long Island Sound earlier in the day. He was sitting at his dining room table, smoking a cigarette.

It was a jarring contradiction for a man whose restaurant, Miya’s Sushi, is renowned for its heart-healthy sushi creations, often made with invasive species of marine life and seaweed as well as weeds scavenged from his overgrown garden. But Lai is a bundle of energetic contradictions.

He bills his restaurant, a few blocks from Yale University in New Haven, Connecticut, as the first sustainable sushi restaurant on Earth.

The menu includes invasive wild boar from Texas, a roll called sushi salaam dedicated to a “world without violence and retribution,” as well as a dish with dried crickets emerging from rice.

“This is our climate-change dish,” he said. He had formed a six-inch-wide puck of frozen seawater from the Sound. It was mixed with invasive seaweed, also from the Sound, and salt from the Pacific island nation of Kiribati, which is struggling to stay above the rising sea levels. He placed the puck atop a water jug with a candle at the bottom. The puck glowed and cast green shadows onto a thinly sliced island of invasive lionfish.

Lionfish is native to Kiribati, Bun said, but the fish he serves was caught in Mexico. After being released into the wild by aquarium owners, the Pacific fish has spread to the U.S. Southeast and throughout the Caribbean. Without any natural predators, it is crowding out many native species.

To him, serving the lionfish speaks to eating animals and plants in concert with what nature provides rather than forcing nature to provide what we want.