How to Read the Seafood Counter Like a Marine Biologist
How To Protect The Ocean
Picture a big sign over the seafood counter promising sustainable fishing, with a fish every independent guide says to avoid sitting on ice right below it. In most countries nobody broke a rule, because the word "sustainable" on seafood has no legal definition. In this final episode of our sustainable seafood week, Andrew Lewin walks you through how to see past that sign and choose seafood you can feel good about. You'll learn how to use the eco-labels and seafood guides that have already done the research for you, including the Marine Stewardship Council's blue tick for wild seafood, the...
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Is Bottom Trawling Always Bad? It Depends Where
How To Protect The Ocean
Off the south coast of England, about 100 kilometres out, sits Haig Fras, a granite reef covered in jewel anemones and cup corals. For years it was protected on paper, yet heavy fishing gear could still drag across it. In March 2024, that finally changed. In this episode, Andrew Lewin explains why where we fish matters as much as how much we fish, and what it takes to turn a line on a map into real protection. Andrew breaks down the difference between midwater and bottom trawls and puts the damage shown in the recent Ocean documentary into context. Bottom trawling lands about a quarter of the...
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The Trapdoor That Saves Sea Turtles From Shrimp Nets
How To Protect The Ocean
A Kemp’s ridley sea turtle, the most endangered sea turtle on Earth, gets swept into a shrimp trawl. It hits a metal grid, slides out through a flap in the net, and swims away. That small trapdoor, the turtle excluder device, is one of the biggest success stories in fisheries management, and in late August 2026 a US federal appeals court upheld the rule extending it to skimmer trawl boats 40 feet and longer. In this episode, marine biologist Andrew Lewin walks through the bycatch fixes that are working and the fights still underway. You’ll hear why North Atlantic right whales get tangled...
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The Cod Came Back: What a Fishery Collapse Teaches Us About Overfishing
How To Protect The Ocean
Five centuries ago, explorers off Newfoundland described cod so plentiful that a weighted basket lowered into the sea came back full. By July 2, 1992, so few remained that Canada shut the northern cod fishery overnight. About 30,000 people lost their work in what became the largest single layoff in Canadian history. In this first episode of a week-long sustainable seafood series, Andrew tells the story of how the collapse happened and how slowly the cod came back. Andrew then breaks down the words that cause the most confusion in fisheries headlines: overfishing, overfished, depleted, and...
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How to Choose Sustainable Seafood
How To Protect The Ocean
You want to eat seafood the right way. Then you hit the seafood counter and face a wall of labels, a sign promising “sustainable practices,” and an employee who has no idea where the tuna came from. Add documentaries like Seaspiracy telling you to quit fish entirely, and it’s tempting to give up and buy whatever looks good. Unsustainable fishing is the biggest threat to marine biodiversity, so those choices carry real weight. In this episode, Andrew’s good friend Dr. David Shiffman joins the show to talk about his new book, Why Sustainable Seafood Matters. David spent two years on the...
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Slow Down for Whales: How Global Shipping Learned to Share the Ocean
How To Protect The Ocean
Blue whales can’t dodge ships. When scientists tracked blue whales alongside cargo ships off Southern California, the whales responded in just over half the encounters, and every response was the same: a slow, shallow dive. Not once did a whale move sideways out of the ship’s path. Models suggest ships kill around 18 blue whales a year off the U.S. West Coast, nearly eight times what the population can lose and still recover. The good news is in the data. Most blue whale strike deaths happen in a small slice of ocean, and that’s where ports, air quality agencies, marine sanctuaries, and...
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When Whale Food Moves: Climate Change, Crab Traps, and Pop-Up Gear
How To Protect The Ocean
In 2014, a patch of unusually warm water nicknamed "the blob" settled off the west coast of North America. The cold, food-rich water that normally stretches far offshore shrank into a narrow strip along the coast, and hungry humpback whales followed their food straight into the waters where Dungeness crabbers had set thousands of traps, each tied to a vertical rope. Entanglements jumped from about 10 a year to 53 in 2015 and 55 in 2016. In this episode, Andrew traces the line from warmer water to a specific whale in a specific rope. You'll learn why lunge-feeding whales depend on dense patches...
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The Whale Heart That Beats Twice a Minute
How To Protect The Ocean
Fill your hands with cold water, hold your breath, and press your face in. Your heart slows within seconds. That reflex lives in every whale in the ocean too, and in a blue whale it is pushed so far that the largest heart on Earth can drop to two beats a minute on a deep dive. In this episode, Andrew walks through the first heart rate recording from a wild blue whale, led by Jeremy Goldbogen's team at Stanford, and a study by Terrie Williams of UC Santa Cruz that tracked narwhals fleeing after release from nets in East Greenland. The narwhals swam as hard as they could while their hearts fell...
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The Biggest Mouthful: How Blue Whales Eat and Why Krill Matters
How To Protect The Ocean
A blue whale can swallow a volume of water bigger than its own body in a single gulp. That move, called lunge feeding, is one of the most extreme feats in the animal kingdom, and it only pays off when krill is packed into thick, dense swarms. In a thin patch, a blue whale gets back about six times the energy it spent. In a dense swarm, it gets back more than 200 times. In this first episode of the Age of Giants series, Andrew breaks down how rorqual whales feed, then follows the krill. In 2025, the Antarctic krill fishery hit its 620,000 tonne precautionary limit for the first time and closed...
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Whales Are Sprinters: What a Blue Whale's Heart Does When It Lunge Feeds
How To Protect The Ocean
What happens to the heart of the largest animal on Earth when it charges into a swarm of krill? Dr. Ashley Blawas, a postdoctoral scholar in Jeremy Goldbogen's lab at Stanford's Hopkins Marine Station, joins Andrew to unpack new research published in PNAS that measured the heart rates of lunge-feeding blue whales and humpback whales using suction-cup ECG tags. Ashley explains the three phases of lunge feeding (accelerate, engulf, filter) and why these giants behave a lot like human sprinters. Their heart rates stay high after each lunge, then gradually recover while they glide and filter,...
info_outlineBacteria that eat plastic sounds like the fix everyone's been waiting for, and Andrew gets sent videos about it constantly. So on this solo episode, following Monday's interview with Dr. Anja Brandon of Ocean Conservancy, he goes looking for the real state of the science. The short version: it's promising, it's roughly a decade of real research deep, and it is nowhere close to running at the scale the ocean plastic crisis actually needs.
The bacterium that started this whole field, Ideonella sakaiensis, was discovered breaking down PET plastic in Japan in 2016. A 2025 breakthrough from NREL, UMass Lowell, and the University of Portsmouth engineered an improved PET-degrading enzyme that cut chemical use by more than 99%, running costs by 74%, and energy use by 65%, modeling out to a cost that actually undercuts virgin plastic. It's a genuinely exciting result. It's also still lab-stage, with no commercial plant running it yet. Carbios, the French company furthest along at trying to bring enzymatic PET recycling to industrial scale, is proof of just how hard that jump is: its flagship French plant is delayed, its cash reserves have been cut by more than a third, it slashed 40% of its workforce, and it's now pivoting toward a joint venture in China that's faced its own shareholder disputes.
Then there's the other technology people call "plastic-eating," chemical recycling through pyrolysis, which isn't biological at all. It's plastic melted down with extreme heat back into oil and gas, currently handling under 1.3% of US plastic waste according to advocacy group Beyond Plastics, regulated by the EPA as a form of incineration (a classification the agency is actively trying to change as of this year), and excluded from the EU's own definition of recycling entirely. Andrew lays out where the real hope sits, where the hype outruns the evidence, and why reduce, reuse, and refuse still does more for the ocean than any of this, at least for now.
Takeaways:
- The bacterium behind the "plastic-eating bacteria" field, Ideonella sakaiensis, was discovered in Japan in 2016, and the research is real but still roughly a decade from meaningful commercial scale.
- A 2025 enzyme breakthrough from NREL, UMass Lowell, and the University of Portsmouth models out to costs that undercut virgin plastic, but it's a lab and modeling result, not a running commercial plant.
- Carbios, the company furthest along at industrial-scale enzymatic PET recycling, still can't get its flagship French plant operational and is now pivoting toward a contested joint venture in China.
- Chemical recycling (pyrolysis) is a separate, non-biological technology that melts plastic down with heat, currently handles under 1.3% of US plastic waste, and is regulated by the EPA as incineration, a classification the agency is actively trying to change in 2026.
- Advocacy group Beyond Plastics found pyrolysis facility emissions can run 10 to 100 times higher than making virgin plastic, and that multiple US pyrolysis facilities have already shut down or gone bankrupt.
- None of these technologies are close to solving ocean plastic pollution at scale right now; reducing single-use plastics at the source still does more, and that requires government leadership, not just individual habit changes.
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