Drifting crustaceans could hold key to climate change

Drifting crustaceans could hold key to climate change - University of Exeter

Calanus finmarchicus - a copepod that plays a crucial role in the ecosystems of the North Atlantic and Arctic oceans. Credit Prof Daniel J Mayor @oceanplankton

The vast quantity of tiny animals in the global ocean could play a vital role in slowing climate change, scientists say.

The ocean contains a huge variety of zooplankton (literally meaning “drifting animals”) including copepods – tiny crustaceans thought to be the most numerous multi-celled organisms on Earth.

Mostly feeding on micro-algae called phytoplankton, this army of drifting crustaceans may help to store enormous amounts of carbon in the ocean – keeping carbon out of the atmosphere and slowing climate change.

Three ambitious new projects have now been funded by the Natural Environment Research Council (NERC) BIO-Carbon programme to investigate this.

“The global ocean is absolutely teeming with living organisms, many of which are difficult or impossible to see with the naked eye,” said Professor Daniel Mayor from the University of Exeter, which is involved in all three projects. “But don’t be fooled by their size – these tiny but mighty lifeforms play a crucial role in regulating Earth’s climate by moving carbon out of the atmosphere and shunting it down into the deep ocean where it says for hundreds of years or more. A major thrust of the BIO-Carbon research within Exeter is focussing on marine copepods, miniature relatives of crabs and lobsters. We’re examining how these important animals influence the ways in which the ocean absorb atmospheric carbon dioxide – and how things may change in the future.”

Recent evidence suggests climate models are not fully accounting for the impact of marine organisms – and this could hinder predictions of the ocean’s role in future carbon storage.

“It’s not just the healthy living marine life that the projects will be studying, but also the sick and virally infected cells,” said Professor Mike Allen, of the University of Exeter and co-founder of Seaweed Generation Ltd, a UK startup which utilises marine robotics for carbon removal. “In recent years viruses have dominated people’s lives. They have an even bigger impact in the ocean, where marine life is busy dying from the impacts of viral infection on a staggering scale. With more than a million viruses per millilitre of seawater and a well-mixed soup of potential hosts around them with no way of isolating themselves, the impact of viral infection on global carbon cycling is enormous.”