Sea Urchins: The Marine Vacuum Cleaners

Red, purple, olive green, brown, black… sea urchins have many shades! With more than 900 different species, they also vary in size and can be tiny, small, or very big! But there is one thing they all have in common—their spikes.

Sea urchins are slow-moving, sea-loving animals that are part of the “spiny skinned” family (in scientific language: Echinodermata). It’s understandable why scientists gave them this name! Urchins’ bodies are covered with long spines, which actually move and help them walk and protect them from enemies.

Sea urchins can be found on the bottoms of all seas, except for the cold ones in the polar areas. Usually, when living on the seafloor, they cluster around hard surfaces like rocks.

The funny thing about sea urchins is that they don’t have a recognizable face, but instead have a mouth and a butt!

They are omnivores, which means that they eat plants and animal meat. Their diet consists mainly of lots of algae, seaweed, and plankton from nearby underwater rocks and corals. They also eat the decomposing matter from fish at times. That makes them an important part of our environment because they feed on dead organisms and help to recycle materials into usable energy for other organisms. They are just like underwater spiky vacuum cleaners!

What’s more, they eat the macroalgae, which usually suffocate nearby corals when their populations grow excessively. Without sea urchins protecting the corals, algae will take over and will make it harder for corals to get the light they need to thrive.

But just like anything in nature, there can be too much of a good thing. When we have too many sea urchins, they can destroy seaweed and kelp forests— an occurrence that is actually happening in California.

Luckily for us, sea urchins are very delicious seafood—and by removing urchins that are a little too numerous from the ocean floor and ranching them on land, we can enjoy them AND support their ecosystems! With a beautiful umami taste and a richness in ocean salt, we can eat them the same way we eat oysters and sushi. Or we can pair them with some herb butter and brioche bread—a yummy combination!

In addition to being delicious, sea urchins are also rich in protein, fiber, zinc, beta carotene, and vitamins C and A. Just like our sustainably-grown salmon, they are high in omega-3 fatty acids.

Get better acquainted with sea urchins by printing out our coloring pages and checking out these recipes with sea urchins! Would you like to taste any of them?