How a Tiny Crustacean in Antarctica May Be the Key to Saving the Planet

Friday, 09 Dec, 2022

Krill are a keystone species in the delicately balanced ecosystem of the Antarctic. They’re the primary food source for whales, penguins and seals in Antarctica, and remove carbon dioxide from the atmosphere by eating carbon-rich algae near the surface and excreting it when they sink to lower, colder waters, helping to mitigate climate change. 

Penguins in Antarctica, photo by Barbara Veiga/Sea Shepherd.

Why Krill Are So important

The tiny, shrimp-like crustaceans known as Antarctic krill (Euphausia superba) are the unsung stars of the Antarctic eco-system. Making up the largest biomass of any other animal on the planet, they consume phytoplankton at the water’s surface in summer, and the algae that grows on the underside of the Antarctic ice sheet in winter. Once full, they sink deep into the depths of the cold water where they release the carbon they’ve eaten as feces that remains on the seafloor, creating one of the biggest carbon sinks on the planet. They do this over and over throughout their lives, removing carbon from the surface and sequestering it below like a conveyor belt, removing 23 million metric tons of carbon each year within the Southern Ocean, the amount of carbon produced by about 35 million gas-powered cars (11).

Not only do krill mitigate climate change, they’re also the primary food source for the Antarctic’s birds and marine mammals, including whales, penguins, seals, squid, and fish. To put it simply: without krill, the Antarctic’s delicate eco-system would collapse. And the fallout from losing those carbon sinks, not just from the krill, but from all of the other animals that feed on them, directly or indirectly, is chilling to consider.

Antarctic krill, photo by Uwe Kils (Creative Commons license).

You may be thinking, "Krill, yawn." But no krill = no food for marine birds and mammals in Antarctica. No krill = loss of a major source of carbon sequestering.  "Antarctic krill may be small, but they play a vital role in supporting the Southern Ocean ecosystem."

Nicole Bransome, The Pew Charitable Trusts

Krill provide 96% of calories for seabirds and mammals in the Antarctic Peninsula (1):

* Baleen whales -- such as the giant blue whales, fin whales, sei whales, minke whales, and humpback whales -- consume between 34 million and 43 million tons of krill per year in the Southern Ocean.

* All penguin species feed on krill, but it’s an important part of the diet of emperor, gentoo, bridled, chinstrap, Adélie, macaroni, and rockhopper penguins, each consuming an average of one kilo per day. The chinstrap penguins in the South Sandwich Islands eat 4000 tons of krill per day, and the Adélie penguins in the South Orkney Islands eat 9000 tons of krill and fish larvae each season while raising their chicks.

* Antarctic fur seals, Ross seals, leopard seals, and especially crabeater seals, who consume 50 to 150 million tons of krill per year alone.

* Several species of Albatross, petrels, prions and other marine birds

* Also some species of squid and fish, including icefish

And yet…krill populations in Antarctica are already under threat, and it’s only getting worse.

They may be small individually, but there is an estimated 400 million tons of Antarctic krill in the Southern Ocean as estimated in 2021 (2). This sounds like a lot, but krill populations have actually declined by 80% since the 1970s (4).

Climate change affecting the polar caps means Antarctica’s ice shelves are melting. We’ve seen images of polar bears in the Arctic unable to swim the long distances between icebergs, and penguin colonies producer fewer chicks in Antarctica as the ice melts earlier each season. But what you don’t normally see is how the reduction of ice packs in Antarctica, where krill lay their eggs and feed in the winter, are already having an effect on their populations. And this is only expected to worsen as the average temperature rises year after year. We know protecting krill populations can help mitigate climate change, but they’re also among its first casualties.

A crabeater seal on the ice in Antarctica, photo by Simon Ager/Sea Shepherd.

And yet…humans are consuming more krill today than ever before, and the demand is only rising. 

Historically, krill has been consumed in Russia and Southeast Asian countries, either stir-fried and added to many traditional dishes (called okiami in Japan), fermented then ground up and sold as shrimp paste (called Bagoong alamang in the Philippines), or used in liquid form for fish sauce condiments.

But over the past two decades, the demand for krill has more than doubled because of the booming – and highly lucrative -- aquaculture and health supplement industries.

As the demand for fish keeps rising worldwide and fisheries are increasingly overfished, krill is being used by the aquaculture industry to supplement the fishmeal for farmed fish, particularly salmon. Consumers thinking they’re protecting marine wildlife by consuming farmed fish don’t realize they’re still indirectly consuming wild caught fish and krill used in the feed.

Likewise, in the early 2000s the krill industry found out they could package and sell krill oil supplements to western consumers looking for “pure” alternatives to fish oil omega-3 fatty acid supplements. The supplement industry as a whole is booming, and the market for Antarctic krill oil supplements is predicted to rise steadily over the next decade.

As the industry looks to diversify their markets, you’ll also find krill sold as fish bait, livestock feed, and pet food (including food for aquarium fish).

Sea Shepherd Spotted the Krill Trawlers During Anti-Whaling Campaigns in Antarctica 

Sea Shepherd sounded the alarm in 2013 when our crew in the Southern Ocean spotted the massive krill fishing trawlers while battling Japanese whaling vessels (read Krill Fisheries: The Next Collapse?). A loss of krill in the waters of the Antarctic could potentially do more to harm whale populations in the long term than even the Japanese harpoon ships. 

"A decline in krill will eventually hit all animals in the Antarctic, even flying birds and fish, and will prevent the great whales from returning to pre-exploitation numbers."

An April 2013 Sea Shepherd commentary from the Southern Ocean.

Krill Fishing in Antarctica

Fishing in the remote Antarctic waters is challenging and expensive because of the extreme conditions and distances ships must travel. But because Antarctic krill live in large schools called swarms, sometimes reaching densities of 10,000-30,000 individuals per cubic meter, it's easy for fishing vessels to scoop up large quantities in one location.

Fishing activities in Antarctica, including for krill, are regulated by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) established in 1982. Although they set “precautionary catch limits” in the 1990s to prevent overfishing of krill, many scientists consider these quotas to be outdated (the last survey was in 2006), and inadequately take into account the effects of climate change and the technological advances of the krill-fishing fleet.

Because of climate change, changes in sea ice and rising temperatures mean vessels can stay longer and fish in areas that used to be covered in ice. A recent investigation into the global fishing industry by the Environmental Reporting Collective found that catch limits for Antarctic krill were reached in just 69 days, as opposed to an average of 130 days over the previous five years (7).

In addition to more “efficient” fishing methods (essentially underwater vacuums that suck up massive quantities of krill), these fisheries also hurt Antarctica’s environment and marine wildlife through bycatch of non-target species such as whales. A humpback died this January in the net of one of a Norwegian krill-fishing vessel, and three juveniles were killed by the same company in 2021 (8).

The presence of industrial trawlers pollutes this once-pristine environment through emissions, oil spills, the loss or dumping of deadly fishing gear, introduction of invasive species through biofouling, and the humanitarian and environmental effects of illegal, unreported and unregulated (IUU) fishing.

Whales in Antarctica with the M/Y Steve Irwin in 2010, photo by Barbara Veiga/Sea Shepherd.

The Major Players in Antarctica’s Krill-Fishing Boom

Norway dominates the worldwide market, with more than half of all krill caught by one company, Aker BioMarine, owned by the Norwegian billionaire Kjell Inge Røkke. In addition to krill, Aker BioMarine makes it profits in oil and gas, construction, marine biotechnology and energy. After Norway, other countries fishing in Antarctic waters over the past decade are China, South Korea, Japan, Russia, Ukraine, Poland, and Chile (3).

South Korea is currently registering more ships. China, which more than doubled its catch of Antarctic krill from 50,423 tons in 2019 to 118,353 tons in 2020, has commissioned the world’s largest Antarctic krill trawler, due for delivery in 2023. Even the notorious Chinese distant-water fishing firm Pingtan Marine – called out for its squid-fishing fleet just outside the Galapagos National Marine Park by Sea Shepherd last year (watch video)-- plans on entering the lucrative krill fishing industry.

Russia, which once dominated the Antarctic krill fisheries in the 1980s under the Soviet Union, has also invested $640m in krill fishing, including five new high-tonnage trawlers (7). This is disturbing because any decisions made by CCAMLR need to be unanimously approved by its members, and Russia has consistently joined China in vetoing any new MPS in Antarctica since 2017 that would affect krill fishing in any way. They did it again last month at the CCAMLR’s annual convention, insisting that it’s in the krill-fishing industry’s own best interest to manage themselves in a sustainable manner.

Conservation Measures Falling Short

However, the voluntary industry agreement where some – but not all – of the krill fishing trawlers have promised to avoid trawling in certain -- but not all -- sensitive areas during certain seasons, has already been called into question because they are neither monitored nor enforced. So not only are these voluntary measures limited in their effectiveness, they’re also used by the krill industry to preempt more stringent MPAs that would apply to all fishing activities (12).  

CCAMLR’s Scientific Committee has recommended that observers should be placed on 100% of Antarctic krill fishing vessels (there are currently 10-15 krill fishing vessels in Antarctica each season), but this won’t achieve much if the quotas are too large to begin with.

What about Certified Sustainable Krill?

Unfortunately, there’s heavy greenwashing in the krill supplement market. NGOs and scientists have raised the flag about certification schemes like the Marine Stewardship Council (MSC) and Friend of the Sea (FOS), which were found to be certifying numerous fisheries as sustainable even when they were overfished, had high levels of bycatch and, in some cases, were even at odds with national legislation.

The Pew Environment Group has criticized MSC for certifying Antarctic krill as early as 2010. “Unfortunately, perception is reality,” said Gerald Leape, director of Pew's Antarctic Krill Conservation Project (AKCP). “The MSC's label falsely advertises the message that all krill are sustainably caught and that consuming krill-based omega 3 supplements or purchasing farmed salmon raised on krill meal is okay. Nothing could be further from the truth.” (9). They pointed out three key issues which were not taken into account in the MSC’s certification: the potential effects of climate change, the impact of all the concentrated fisheries targeting krill in the Antarctic, and the limited understanding of krill’s life cycle and its importance to the local food web

In 2021, several more NGO groups joined the Pew Charitable Trusts calling out Aker BioMarine for using a 2019 study to demonstrate the health of krill stocks which failed once again to reflect the true cost of the fisheries on the marine wildlife, both directly and in the face of climate change.

Some krill-fishing companies even go as far as to make up their own certifications. Aker BioMarine krill products prominently display the so-called ‘Eco-Harvesting’ label, which ‘certifies’ that the krill was caught using the Aker BioMarine ‘eco-harvesting method’, which is a fishing method developed and patented by Aker BioMarine that allows fish to be caught continuously without needing to retrieve the nets (10).

An albatross in Antarctica, photo by Simon Ager/Sea Shepherd.

The Warning Signs Are Already Here

Penguins are considered to be the proverbial canaries in the Antarctic coal mine, and their populations are already suffering due to climate change. A 2018 study co-authored by George Watters, lead scientist for the US government delegation to CCAMLR, warns that climate change could reduce krill size by up to 40% in some areas of Antarctica’s Scotia Sea, resulting in a 30% drop in penguin populations (5).

In 2016 Antarctica’s second largest colony of emperor penguins collapsed and more than 10,000 chicks died when the strongest El Niño in 60 years caused heavy winds and record-low sea ice. Earlier this year, new gentoo penguin colonies were discovered further south in Antarctica than ever before, where the ice has receded. These areas were previously too cold for gentoo penguins, which prefer more temperate climates such as the Falkland Islands to raise their chicks (6).

According to a report this January by Global Industry Analysts, the $531-million market for krill oil is projected to rise to $941 million by 2026. Fish farming (which uses krill as feed), is the world's fastest growing food sector, as global demand for fish is expected to double by 2050 (8).

In the face of climate change, do we really want to risk putting additional pressure on krill populations by expanding krill fishing for fish food and omega-3 supplements for humans?

What Can YOU Do Today to Take Action?

The easiest way to help protect the Antarctic and the marine wildlife that call it home is to stop buying krill-based products, including krill oil health supplements (there are many vegetarian and vegan alternatives), and farmed fish. As it’s so difficult to trace exactly what ANY farmed animal sold in stores and restaurants is fed, or the true origin of fishmeal used to feed so many farmed animals, Sea Shepherd recommends removing animal products from your plate altogether if you really want to make a difference for the ocean. Not everyone on the planet has the option to eat a plant-based diet – -- including the animals living in the ocean -- so for those of us who do, there are no excuses.

Learn More

Some additional resources to check out include:

Solutions to Protect Antarctica’s Keystone Species by Pew Charitable Trusts (also scroll down to see their video)

Krill, Baby, Krill: The corporations profiting from plundering Antarctica by Changing Markets Foundation

- Scroll down past the video for all of the sources cited in this article. 

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