Starfish, also known as sea stars, are invertebrate animals found on the ocean floor or attached to rocks. But can they swim?
Starfish move around by extending their tube feet and using them to crawl. They do not have the ability to swim actively, but they can use their tube feet to propel themselves through the water.
How do they get around?
The Water Vascular System (WVS) is used by Sea Stars and other Echinoderms to move around. It is composed of several canals that connect the tube feet at the underside of their bodies. These tube feet possess small suction cups, enabling them to attach to objects like rocks or corals.
The suction effect of sea stars also enables them to open their prey’s shells.
The WVS creates contractions in the body of these animals by using seawater pressure. The contractions help with movement, both for clinging onto objects and for actively moving across surfaces. The WVS can also be used to expand or retract certain parts of a starfish’s body, allowing it to fit into tight spaces, swim, climb and dig into the sand.
What is the water vascular system?
It’s a circulatory system of sea stars. Water enters via the madreporite and flows to the stone canal. This links to a ring canal at the center of the starfish body. The radial canal links from this, running through each arm and ending in a terminal tentacle.
Canals are equipped with sluice gates to prevent any backward flow, and they have lateral canals as well.
These lead to ampullae in each tube foot, producing contractions for climbing or movement. It also exchanges gases and nutrients. It helps sea stars move and survive!
The Free-Swimming World of Starfish Larvae
Starfish can swim at one point in their lives. It happens during the larva stage. Males and females release their eggs and sperm, which are then fertilized.
The fertilized eggs become larvae, part of the plankton. They drift in the water until metamorphosis occurs, and they transition into sea stars.
During that time, they actually swim using motions such as a rocking motion or by widening/closing their arms to move along.
That’s why you sometimes see them gliding along the ocean floor—they’re swimming! When they reach their final form, they settle onto the bottom of the seabed and embark on life as adult starfish.
How Quickly do They Move?
What’s slow? Starfish. Yes, starfish are some of the slowest creatures on Earth, right behind three-toed sloths and garden snails.
Species and conditions affect their speed, but the fastest recorded one is the Sand Starfish (Luidia foliolata) which moves up to 9 feet/per minute. The slowest is a Leather star (Dermasterias imbricata) traveling at only 15 inches/minute.
On average, they move 3 feet/min with their 15,000 tube feet, according to NOAA. Even so, it’s not enough for us humans to notice!
Why do Starfish Move Around?
Sea stars are animals like humans and all the creatures on the planet. They normally feed on mollusks, such as clams, mussels, and oysters. Some species also consume corals or dead organic matter, making them important decomposers in the ocean.
They move to find food, just like us. Sea stars use their tube feet to help them along. These tube feet have suction cups and underneath them is a hydrostatic skeleton that helps provide movement for these chilly creatures!
Unlike most animals that require oxygen to stay alive, sea stars don’t need it. They do not breathe in oxygen through their gills or lungs but get glucose from photosynthetic algae instead.
Sea stars survive in different environments provided they have food sources such as coral reefs, rocky shores, and sandy bottoms of oceans. Generally, they prefer cold water, although some species thrive in warm waters too.
The color of a sea star greatly depends on its habitat and, at times, changes over time as it gets older or reaches maturity age. The vibrant blue with yellow stripes is a distinctive feature of adult sea stars which can be found near shallow waters around tropical seaside regions.
All these features make them amazing creations by Mother Nature!
How Regularly do They Move?
Starfish don’t move a lot. Frequency depends on species and conditions. About 2,000 species of sea stars exist, and they adapt to different environments. They can be small or have different amounts of arms.
Some hide in the sand, while others are active and search for food. To protect from predators, starfish attach themselves to rocks.
The most active time is eating. Tube feet open shells of prey, and the stomach enters inside. Eating time is when movement is at its peak.
Overall, starfish don’t move continuously but show more activity during feeding time.
Important Facts and Overview
Starfish reproduce both sexually and asexually. During larval development, starfish undergo a larval stage where they develop organs as well as their adult coloring. Some types of starfish are able to reproduce solely through asexual reproduction, while others must use sexual reproduction.
Their ability to swim allows them to traverse different habitats and feed on prey located there. During Starfishes’ young life, swimming skills can be an important factor in their survival in the marine food web chain. Swimming also allows starfish to move away from danger quickly in case of predators or other threats in their environment.
In summary, starfish do indeed swim! In addition to wandering across the ocean floor like slow-moving snails, this unique marine animal has the ability to make quick singular movements when needed, allowing it to survive in harsh environments by navigating multiple habitats with swiftness and ease.
A common marine animal with hundreds of tube feet and a flexible body, they come in a variety of sizes.