If you take a krill oil supplement, sooner or later a small voice asks the obvious question: am I eating my way through the bottom of the food chain? Penguins eat krill. Whales eat krill. Seals, fish, seabirds — half the Southern Ocean runs on the stuff. So scooping it up by the shipload to put in a softgel feels, on the face of it, like it ought to be a problem.
Here’s the short version, and I’m not going to bury it: no, Antarctic krill is not an endangered species, and by the usual numbers the fishery is one of the more conservatively managed on the planet. Antarctic krill (Euphausia superba) is, by weight, very likely the most abundant wild animal on Earth — somewhere on the order of 379 million tonnes of it swimming around the Southern Ocean. The amount harvested each year is a rounding error against that.
But if you stop there you’ve only heard the part the industry likes to repeat. The honest answer is more interesting than “it’s fine,” and it has changed in the last two years. The thing worth worrying about was never the global total. It’s where the boats fish and what else is trying to eat in the same water — and in 2025 that quiet concern became a real one for the first time. Let me walk you through it the way I’d explain it at the dock.
The short answer: no, krill is not endangered
Start with the biomass, because the scale is genuinely hard to picture. The standard circumpolar estimate for Antarctic krill is roughly 379 million tonnes — a figure from a widely cited re-appraisal of the total stock. That is more biomass than all the humans on Earth combined. It’s a strong candidate for the largest single-species animal biomass anywhere on the planet.
In the corner of the Southern Ocean where almost all commercial fishing happens — CCAMLR’s Area 48, the waters around the Antarctic Peninsula and the Scotia Sea — the most recent large-scale acoustic survey, run in 2019, estimated about 62.6 million tonnes. For context, a survey of the same region in 2000 came in around 60.3 million tonnes. Across nineteen years, in the most heavily fished area, the stock was essentially flat — slightly up, if anything.
Against that backdrop, the catch is tiny. In 2024 the total Antarctic krill harvest was about 500,000 tonnes — roughly 0.8% of the estimated biomass, and well under the precautionary ceiling. The fishery carries Marine Stewardship Council certification, the most recognized sustainability label in seafood. So no — nobody is fishing krill toward extinction, and no serious scientific body lists the species as endangered. If that’s all you wanted to know, you can stop reading and take your capsule with a clear conscience.
If you want the part that actually matters, keep going.
How little we take, and who decides
The body that runs all of this is CCAMLR — the Commission for the Conservation of Antarctic Marine Living Resources, the international treaty organization that has managed the Southern Ocean since 1982. What makes CCAMLR unusual is that it was built from the start around ecosystem-based management: the rule isn’t “leave enough krill to keep catching krill,” it’s “leave enough krill to feed the whales, penguins, and seals that were here first.” That’s a meaningfully higher bar than most fisheries set for themselves.
In practice CCAMLR uses two limits. There’s a precautionary catch limit for Area 48 of 5.61 million tonnes — the theoretical maximum the science says the stock could sustain. But the fishery is never actually allowed to approach that. It’s held back by a far lower “trigger level” of about 620,000 tonnes, which works out to roughly 1% of the surveyed Area 48 biomass. That 1% figure is the number to remember. It exists specifically so that the predators’ needs come first, and the fishery operates in the slim margin left over.
So the arithmetic the industry quotes is real. One percent of a stock that has held steady for two decades, harvested under an international treaty with a predator-first mandate and a third-party eco-label. On paper, this is about as good as commercial fishing gets. The trouble is that “1% of the whole” and “1% of the spot where the penguins are feeding this week” are not the same number — and that gap is where the real story lives.
So why are scientists worried at all?
Two reasons, and they’re separate, so it’s worth keeping them apart.
The first is climate. Antarctic krill depend on sea ice — the underside of the ice is the nursery where larval krill feed through their first winter. As the Antarctic Peninsula warms (it’s one of the fastest-warming places on the planet) and sea ice forms later and breaks up earlier, that nursery shrinks. Long-term observations suggest adult krill in parts of the southwest Atlantic sector have declined sharply since the 1970s, with some estimates of an 80–90% drop in certain regions, alongside a contraction of the population southward toward the remaining cold water. The cause is genuinely debated — some of the apparent decline may reflect recovering whale populations eating more, not fewer krill being born — so I won’t overstate it. But the direction of travel is not reassuring, and recent habitat-suitability modeling projects further contraction of good krill habitat under higher-emission scenarios by 2100. None of that is the fishery’s fault, but all of it shrinks the cushion the fishery is supposed to leave for everyone else.
The second reason is the one that actually changed recently, and it has nothing to do with the global total.
The real issue is where, not how much
Here’s the thing the biomass headline hides. The krill fishery doesn’t spread its 620,000 tonnes evenly across the Southern Ocean. The boats go where the krill is densest and the weather allows — and that’s increasingly a few narrow channels around the Antarctic Peninsula, places like the Bransfield and Gerlache Straits. These are exactly the waters where chinstrap and gentoo penguins, and humpback and fin whales, concentrate to feed and raise their young.
When fishing piles up in the same small patches that breeding predators depend on, you get what scientists call localized depletion: the regional total looks fine, but a penguin foraging within range of its nest finds the cupboard bare at the wrong moment. Research in the Western Antarctic Peninsula has linked fixed catch limits in low-krill years to reduced breeding success in Pygoscelis penguins. A predator can’t fly to the other side of the Scotia Sea to find the “other 99%.” It eats where it nests, or it doesn’t feed its chick. This is the failure mode that a single big biomass number cannot see.
For sixteen years CCAMLR managed this risk with a measure called CM 51-07, which spread the catch limit across sub-areas so the fleet couldn’t pile its whole quota into one penguin neighborhood. Then, at the 2024 meeting, members failed to renew it and the measure lapsed. From the 2025 season on, there were no longer spatial rules governing where that ~620,000-tonne limit could be taken.
The result showed up almost immediately. In the 2025 season, heavy sea ice pushed the fleet off its usual grounds and into Subarea 48.1 around the Peninsula, where the catch hit roughly 358,000 tonnes — more than double the ~155,000-tonne norm that had held under CM 51-07. In August 2025, the fishery reached the trigger level for the first time in its history and was shut down for the season. Industry groups argued, fairly, that the automatic closure proves the safety system worked. Conservation scientists countered, also fairly, that hitting the cap while concentrated in penguin-critical water is precisely the scenario CM 51-07 existed to prevent.
What happened at CCAMLR in 2025 — and what to watch
You’d hope the 2025 CCAMLR meeting fixed it. It didn’t. The annual meeting closed without consensus on a replacement spatial measure or on long-discussed marine protected areas. CCAMLR runs on full consensus, so a small number of members can block reform, and there is simultaneous pressure in the other direction — Norway and China have pushed to expand krill harvesting, citing the healthy total biomass. Researchers writing in PNAS in 2025 have argued the management approach needs modernizing to handle exactly this century’s pressures: climate-driven shifts in where krill live, and a fleet that concentrates rather than spreads.
So the honest 2026 status is this. The species is abundant and not endangered. The total harvest is genuinely small. And yet the management framework that kept that small harvest from landing on top of breeding penguins has frayed, and the political will to repair it isn’t there yet. “Is krill sustainable?” has quietly stopped being a question about arithmetic and become a question about governance.
How to buy krill oil without kidding yourself
None of this means you have to give up your omega-3s in guilt. It means the sustainability question has a real answer that depends on who caught your krill and where they’re willing to tell you it came from — not on a green leaf printed on the box.
A few fair questions to ask any krill oil brand: Is the krill MSC-certified? Is the supplier a member of the Association of Responsible Krill harvesting companies (ARK), whose members observe voluntary buffer zones and seasonal restrictions around predator colonies beyond what the lapsed rules required? Can they tell you which CCAMLR subarea and season your batch came from? A company that sources responsibly can answer all three without flinching. A company that can’t will change the subject to how big the krill biomass is — which, as you now know, is the part of the answer that was never really in doubt.
A note on Captains Krill Oil™. We source our krill exclusively from CCAMLR-regulated, MSC-certified Antarctic fisheries, and we keep catch documentation — the subarea and season your krill came from — available on request. We say this not to sell you on a feeling, but because the whole point of this article is that “it’s sustainable” is a claim that should come with paperwork. The krill biomass is enormous; that’s the easy part. Whether your supplement was taken in a way that left room for the penguins is the part that actually requires an honest supplier — mechanically extracted, no chemicals at any stage, sourcing documentation available on request. That’s the standard we hold ourselves to, and it’s a fair one to hold us to