"Tiny Zooplankton Play a Vital Role in Combating Climate Change"

Sun Oct 19 2025 09:03:39 GMT+0300 (Eastern European Summer Time)

"New research reveals how small marine creatures are pivotal in locking away carbon emissions."

"Zooplankton, often unrecognized, significantly contribute to carbon sequestration in the Southern Ocean. Their migration and fat storage can counteract climate change impacts by absorbing carbon equivalent to emissions from 55 million cars, but they face increasing threats."

A new study highlights the crucial role played by tiny, often overlooked marine creatures known as zooplankton in the fight against climate change. These diminutive beings, sold mainly as aquarium food, engage in a remarkable seasonal migration that helps sequester massive amounts of carbon. According to researchers, zooplankton gorge themselves on phytoplankton in spring, then descend deep into the Antarctic Ocean, where they burn off their fat reserves. This process locks away carbon equivalent to the annual emissions of approximately 55 million petrol cars.

Research led by Dr. Guang Yang and supported by the British Antarctic Survey emphasizes the need to reconsider the carbon storage capabilities of the Southern Ocean. Dr. Jennifer Freer, a co-author, describes the zooplankton's lifestyle as "remarkable" yet notes that they often remain underappreciated when compared to more iconic Antarctic species like whales and penguins. With sizes ranging from 1 to 10 millimeters, copepods—one of the key types of zooplankton—have unique adaptations, including fat storage crucial for their survival during migration.

Globally, oceans have absorbed about 90% of the excess heat from human activities, with the Southern Ocean alone responsible for about 40% of this absorption. This significant contribution is primarily due to zooplankton, which have been captured in ongoing studies using the research vessel Sir David Attenborough. The team's observations indicate that this seasonal vertical migration helps transport around 65 million tonnes of carbon beneath the ocean surface each year.

Despite their vital ecological function, these creatures face escalating threats from climate change, including rising ocean temperatures and commercial krill harvesting, which has seen about half a million tonnes collected in 2020 alone. The loss of zooplankton may hinder the ocean's ability to sequester carbon, urging scientists to include these findings in future climate models. Co-author Prof. Angus Atkinson asserts that if this biological mechanism did not exist, atmospheric CO2 levels would potentially double.

The research findings are detailed in the latest edition of the journal Limnology and Oceanography, illustrating the hidden yet critical role that small marine organisms play in mitigating climate change impacts.