Last updated on February 4th, 2022
Have you heard about the creatures that crawl on the ocean floors? I’ve heard of animals crawling on land, on sea beaches, and even on walls, but on the seafloor!
This was the question that my nephew asked me. I was taken aback because I couldn’t answer it promptly.
Every sea creature that I could think of was a swimmer and didn’t crawl on the floor. But the twinkle in my nephew’s eye told me that several animals crawl in the sea, and there are evolutionary reasons for their behavior.
Animals that crawl in the sea:
- Sea Cucumber
- Sea Turtle
Here are seven of the most common animals that crawl in the ocean:
Starfishes can’t swim, but that doesn’t mean they can’t move.
Instead, they glide along the ocean floor quite swiftly. They can do it by jettisoning water from the tiny tubes attached to the ends of their feet.
The pressure at which the water is released from the tubes helps them detach from the surface and move forward.
Similarly, starfishes can crawl across the rocks in the sea by flexing their tube-like bodies. It bends its tube-like feet to help it move across the rocky surfaces.
Finally, you must have seen a starfish become a dome-like shape, especially when the central part of its body is detached from the rock. In this case, it pumps water in and out of its body.
The pressure created by the jettisoned water helps the starfish to glide on the stone. Similarly, a starfish pumps water in and out of its tube and crawls across the seabed.
Octopuses are invertebrates and belong to the family of mollusks. They’re excellent swimmers but there are a few that prefer to crawl or walk on the ocean floor.
Since octopuses have tentacles, they’ll use them to crawl on the seafloor by tucking them beneath their body while using the arms to push themselves forward.
In an attempt to locate food resources, the octopus uses its tentacles to move forward and across the seafloor while searching for snails, clams, or sea stars to consume.
However, the movement of the octopus is quite dexterous as it crawls across the seafloor.
If it wants to move backward, it squirts out water and uses the tentacles to control the force. Thus, the tentacles help the octopus to move both forward and backward.
Stingrays are cartilaginous fishes that tend to stay closer to the seabed.
If you observe the movement of stingrays, you’ll notice that they don’t swim like other fishes.
The primary reason for this is that stingrays don’t have dorsal fins and pectoral fins. Instead, stingrays move by undulating their bodies and flapping their sides.
The flapping of their sides resembles the flapping of wings but not with the smoothness that birds have.
Thus, their movement resembles that of crawling, and when you see stingrays swim, it appears as though they’re crawling across the ocean floor.
But, don’t think that this means that their movement is slower than other sea creatures.
On the contrary, a stingray can crawl across the seafloor swiftly, and when necessary, it can even use its tail to maneuver its movement.
4. Sea Cucumber
Sea cucumbers are unique marine animals, which usually appear adhered to a spot, but these creatures can move.
Sea cucumbers can crawl across the seafloor, and they do so by changing the water pressure in their feet.
They have five rows of tiny feet that help them move across the sea, and they use these tube-like feet to anchor themselves to the ocean floor.
When they want to move, they increase the water in their feet that help them detach from the spot.
After that, they can crawl across a short distance and attach themselves again onto the ocean floor.
The barnacles that you would see don’t move. These are sessile creatures, which means when they find a suitable place to attach themselves, they’ll stay there for most of their lifetime.
These crustaceans are unique because they don’t change their shells or do anything similar to their fellow crustaceans.
But when these barnacles are small, in some ways, they resemble tiny shrimps or krills.
However, during this time of their life, they have to move around and they’ll crawl across the ocean floor to adhere themselves to a suitable object.
This is the only time during their lifecycle that a barnacle will crawl across the seafloor.
Crabs are unique crustaceans as they have ten legs, but only eight are used for walking while the remaining two front legs are shaped like pincers.
The crabs that live in water are excellent swimmers, and these creatures can even crawl on the ocean floor.
Several species of crabs never come to the surface and spend their entire lifecycle on the ocean floor.
Such crabs can crawl across the ocean floor swiftly. They can do this by coordinating the movement of all eight legs.
The pincers, in the case of crabs, are for balance. When a crab crawls, you’ll find that if necessary, it can move forwards as well.
Here the movement can become a bit cumbersome as the pincers need to be manipulated to move forwards while crabs prefer sideways movements.
If you’ve observed a crab scuttling away, you’ll see that it does that by moving swiftly in a particular side.
A similar movement is followed by crabs that live on ocean floors.
Here too, crabs use their eight legs to move away sideways, especially when running away from danger.
7. Sea Turtle
Sea turtles are heavy creatures and they’re excellent swimmers as well. They use their paddle-like limbs when swimming up, down, and forward.
But sea turtles can even crawl on the seafloor when necessary. Female sea turtles can be found crawling above the high water mark, usually when searching for a nesting spot.
Once hatched, the young sea turtles crawl across the sea beach to the water. The sea turtle is a unique creature because it can swim and crawl with equal skill.
The sea turtle will use its flippers like paddle when it’s underwater while also using it like a pair of forelimbs to crawl when it’s on the sea beach or crawling on the ocean floor looking for food.
The animals that crawl in the sea are starfishes, octopuses, stingrays, sea cucumbers, barnacles, crabs, and sea turtles, however, these creatures also crawl on the sea floors to locate food to consume such as clams, snails, sea stars, and small fishes.