When you think about the Arctic, you probably picture cuties like ribbon seals, narwhals and polar bears, right? While these beautiful animals get all the glory, they wouldn’t be around if it weren’t for me at the base of the food chain!
I’m a tiny crustacean known as the “insect of the sea.” The name “copepod” means oar-footed, and that is exactly how I move around. I use my four to five pairs of legs and even my mouth and tail to swim. In the Arctic, I live on the seafloor, in the water column, on the sea ice surface or in sea ice channels. Trust me, we are everywhere—in the water column, there are more copepods than any other multi-cellular organism!
We come in many forms—some of us are filter feeders, some are predators. All of us have two major life forms and grow by shedding our shell. We go through 12 life stages after hatching—that’s a lot of wardrobe changes!
Did You Know?
Copepods are small, but mighty. We only grow to about 0.3-2 cm long at full size!
There are more than 150 species of us in the Arctic, although you can find us all over the world. The most abundant and largest is Calanus hyperboreus, a filter feeder with red highlights on its antennae. They have a reproductive cycle uniquely adapted to life in the Arctic, using the dark Arctic night for romance. In the deep of winter, males fertilize the females and then die off. Females then survive on stored-up reserves of large fat deposits to make it through the winter.
We are the critical base of the food chain in the Arctic. Even the big guys (like bowhead whales) prey on us! We also are a food source for species like polar cod, which in turn feed other iconic arctic species like ribbon seals. While we might not be as cute and snuggly as the larger, more charismatic critters who depend on them, we are an essential foundation for life in the Arctic.