August 11 is the occasion for a very important holiday – World Krill Day! As the Executive Director of the Antarctic and Southern Ocean Coalition, I’ve learned a lot about Antarctic krill (Euphausia superba) and the critical role they play in Antarctic ecosystems. Since these small creatures often get overshadowed by other Antarctic species, I believe that we should dedicate a whole day to them to boost their public image and raise awareness about their significance. Antarctica’s iconic wildlife like penguins and seals are of course incredibly charismatic.
In fact, when I was lucky enough to go to Antarctica, I couldn’t get enough of watching penguins. However, the species we commonly see represent only a tiny fraction of the unique species that live in the frozen South. In fact, it’s invertebrates like krill that comprise the majority of Antarctic marine life. And despite their modest size (about 6 cm or 2.3 in in length), krill are essential to the functioning of the entire Antarctic marine ecosystem. Here are a few more reasons why krill deserve your attention:
- Antarctic krill are thought to have the largest biomass of any species on the planet, possibly even greater than that of humans.
- Krill annually store the equivalent of carbon produced by 35 million cars
- Almost every species in the Southern Ocean eats krill or eats a species that eats krill.
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Like many Antarctic species, krill are well-adapted to their cold environment. For example, krill larvae survive the cold Antarctic winter by living under sea ice, where they can hide from predators and eat the algae that grows underneath it. The decline in Antarctic sea ice caused by climate change reduces this vital krill habitat and threatens the survival of young krill. Additionally, warming temperatures may also affect krill growth and reproduction.
In addition to these threats there is growing concern about the escalating interest in fishing for krill. Antarctic krill are valued for their high levels of omega-3 fatty acids, which can be used in nutritional supplements. Krill are also used to feed farmed fish, notably salmon and to a lesser extent as a direct source of nutrition for humans. Most of the fishing for Antarctic krill takes place in the Antarctic Peninsula, a hotspot for krill predators. There is a very real threat that krill fishing could cause localized depletion of krill, resulting in very little available for other species in the region. This could put stress on species such as penguins, that are already experiencing the negative effects of global warming, as well as harming the continued recovery of whale species still recovering from whaling in the 19th and 20th centuries.
This is a complex problem, but there are effective solutions. We need to dramatically reduce our global carbon emissions to keep global temperature increases as low as possible. Such actions will benefit Antarctica as well as the whole planet. But we should take action directly in Antarctica as well.
One step is to designate marine protected areas (MPAs) with significant areas closed off to fishing. MPAs have been shown to enhance ecosystem resilience to climate change by limiting the impact of other activities on ecosystems. They also serve as control areas for scientists, who can compare them to areas with human activities to try to figure out what is causing changes. Even when MPAs are created in Antarctica, it will still be important to carefully manage krill fishing to prevent local impacts on species that depend on them.
Although several large MPAs have been proposed in the Antarctic, the countries that govern the region have yet to reach consensus on their creation, despite the urgency of the climate and biodiversity crises. To secure Antarctic protection as a top priority for world leaders, strong public support is essential.
Today, I invite you to take a moment to reflect on the importance of the humble krill. It is vital to raise awareness and spread the message about the urgent need to take action now to ensure a bright future for this tiny animal. By doing so, we can contribute to preserving the delicate balance of the Antarctic ecosystem and protecting the fascinating animals that live in the world’s last great wilderness.
About the author:
Claire Christian is the Executive Director of the Antarctic and Southern Ocean Coalition (ASOC), a coalition of environmental organizations seeking to protect the Antarctic continent and its surrounding ocean. She hopes to make Antarctica’s invertebrates as well-known as its charismatic megafauna..
This is a guest blog and may not necessarily represent the views of other RISE UP network members or RISE UP as a whole. It is only through open dialogue and a diversity of ideas that we will arrive at the solutions necessary to restore Ocean health.