Copepods are unsung heroes in the Earth’s climate. These are tiny shrimp-like creatures, about as small as the tip of a needle, and there are vast numbers of them in the oceans, some of the most abundant creatures on the planet. They’ve been called the wildebeest of the seas because for such small creatures they migrate great distances to forage for food each day, coming near the sea surface to feed at night out of sight of predators, and then sinking deep into the sea during the day. And they also hibernate in winter up to 2km deep in cold seas – one of the greatest migrations on Earth.
Copepods also play a huge part in cycling carbon around the planet. They graze on microscopic algae called phytoplankton, which absorb carbon through their photosynthesis. When the copepods have eaten their fill of phytoplanton, they drop torpedo-shaped droppings deep in the sea, which sink to the seabed and lock away the carbon, preventing it from returning to the atmosphere. And when the copepods die, their carcasses also fall to the seabed and lock away more carbon. So, by removing vast amounts of carbon from the oceans, these tiny creatures are helping to control climate change.