Catlin Arctic Survey: Dr Ceri Lewis talks copepods

WWF is supporting the research of the Catlin Arctic Survey. This year’s research includes an expedition across the ice, as well as an ice base, both in the far north of Canada. The main purpose of the mission is to gather data on the changing Arctic Ocean currents.

Read our previous posts here, here, here, here and here, and an article on the WWF Global Arctic Programme website announcing the launch of the 2011 Catlin Arctic Survey here.

By Dr Ceri Lewis

Copepods: Faster than Usain Bolt. Photo: Martin Hartley, Catlin Arctic Survey

Did you know there are 200 billion more copepods than people on the planet, and even though they are small, their combined mass is over 400 times that of the human population? At their fastest, they travel a hundred times faster than Usain Bolt.

Not only are there a lot of them, they are also essential for the marine food chain. In any food chain there are the ‘primary producers’, life forms that take energy from the sun and turn it into carbohydrates, simple food. In the seas, this is algae, which are anything from single-celled phytoplankton to hundred foot long kelps and meadows of sea grass. This marine plant life does not generally contain the more complex carbohydrates, fats and proteins needed to sustain larger animals.

Tent living. Photo: Martin Hartley, Catlin Arctic Survey

Copepods are secondary producers, gobbling algae gathered by their front three pairs of legs, and turning this into the more complex building blocks needed for larger marine life. They feed at night, avoiding their natural predators of krill, fish and baleen whales.

But copepods are sensitive creatures. They are susceptible to changes in the marine ecosystem. Increased levels of carbon dioxide are being absorbed by the oceans, making them more acid. Dr Ceri Lewis, of the University of Exeter, has just arrived at the Catlin Arctic Base for phase two of the science programme. She’ll be investigating, for the second year, how copepods respond to increased acid levels in the ocean.

When you think of arctic wildlife, threatened ecosystems and climate change, the first thing that springs to mind for many people are polar bears. While they are beautiful creatures, copepods are the stars of Ceri’s research and for good reason: changes in their numbers could have drastic knock-on effects on the health of the marine ecosystem.

Life on the ice base. Photo: Martin Hartley, Catlin Arctic Survey