You’ve Never Seen a Sea Creature Move Like This

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Starfish are fascinating and contradictory creatures – they may look a bit like stars but they are certainly not fish. As you can see in the above clip, they can even walk with a mesmerizing and other-worldly gait. It’s impossible to not be charmed as this amazing creature uses all its appendages to make its way across the sand on a beach in North Carolina. So, let’s take a closer look at how starfish lead their lives and why they move around at all.

What Are Starfish?

So, if starfish are not fish, what are they exactly? They are a type of invertebrate called echinoderms and are also known as sea stars. These animals are in the Asteroidea class, which is the largest class in the Echinodermata family. They are therefore related to sea cucumbers, sea urchins, and sand dollars. There are at least 1,900 different species of starfish, and they do not all look the same. The one in this clip is Luidia clathrata and is a member of a group of “sand stars” called the Luidiidae.

Many sea stars have the classic five-pointed structure and you can clearly see this sea star using its five appendages to move across the sand. People often refer to these as arms but at other times they are called legs or rays. Some starfish have more than 50 arms – they grow more as they get older. Incredibly, if a sea star loses a limb, it can grow it back, but it may take a year or so.

 How Can Starfish Walk?

Sea stars do not have blood. Instead, nutrients are moved around their body using a water vascular system. It is this system that also allows them to walk.

As you have probably noticed in the above video, each leg has thousands of tube feet, called podia, which are actually tiny hydraulic canals. They are connected to a more complex system of larger canals within the body. By contracting and relaxing parts of its body, the sea star can raise or lower its limbs and deploy or retract suction cups at the end of each foot. This allows it to ‘walk’ or to attach itself to a surface. Being able to move is a useful skill, allowing the starfish to find food (they are carnivores) and right themselves if they get knocked upside down.

Their water vascular system functions on dry land as well as in the water, which is why we see this sea star able to walk across the sand. However, the system can only function out of water for so long. Therefore, it was heading back to the sea so that it could survive. This one was lucky. The family shooting the clip gave it a helping hand and placed it back in the sea.

Are Starfish Normally on Sand?

Different species of starfish have evolved to thrive in different habitats. These include tidal pools, rocky shores, coral reefs, and kelp forests. While many of them occupy coastal areas, some can live at depths of up to 20,000 feet. Starfish usually use their ‘walking’ ability to move around underwater and bury themselves in the top part of the sediment or cling to a rock.

They should not be found out of the water on a sandy beach. It is likely that this individual got stuck on the beach by accident. Their sucker system is not that strong, and they can get washed away by large waves and end up stranded on the shore. This one was lucky to be rescued.