Top 10 facts about Starfish

The Sea Star is the alternative name for a starfish as it is not a fish but an echinoderm and it is related to sand dollars or sea urchins. Around the oceans of the world, there are around 2000 species of sea star living in all kinds of climates, from warm to cold waters.

The five armed species of starfish are the most common, but there are species that have many more arms. In fact, there are some that have up to 40 arms.

Starfish have calcified and bony skin which gives them protection from predators. Different species have different colourings including many species that have striking colours so as to warn off predators.

They are strictly saltwater creatures and do not survive in freshwater.

Starfish have the ability to regenerate their limbs and in some cases can regenerate their entire bodies. They can do this as they have most if not all of their vital organs in their arms. However, this does not happen quickly and it will take about a year for a limb to grow back.

Some species of starfish need to have their main body intact in order to regenerate their arms. However, there are some species that need just some of their severed limbs to be intact in order to grow a whole new body.

The majority of starfish have the amazing ability to eat their prey outside of their bodies. They use small suction-cupped tubed feet to open up the oysters and clams that they eat and their stomach then emerges from their mouths and their arms prise open the shell just enough and their stomach then enters it and digests it. Then the stomach then returns to the body. So basically they eat inside out, and this allows them to eat larger prey than they would normally be able to fit into their mouths. Sea stars do not have blood in their bodies. Instead, they have a water vascular system where they pump seawater through its sift plate or majority into their tube feet. Their tube feet are full of seawater and give strength to them. They then use their tube feet to move and to hold their prey.

Starfish have a spot and the end of each of their arms which is a very simple eye that looks like a red spot. The eye can sense dark and light but not a lot of detail.