Starfish Facts for Kids

It is fun presenting facts on the starfish as they are always interested in knowing new things. It is a kind of organism that can keep the kids interested and occupied for a long time as there are at least 2,000 types of them known to the man. Marine scientists have named it as Protoreaster Nodosus for their use. A starfish has no scales, fins or gills, like other fish have to acquire oxygen from the water, and it can't actually swim. For this reason, even though it has 'fish' in its name, marine biology does not consider it as a fish.

Details about the Starfish

Starfish are also known as 'Sea Stars', which is a more apt name for them. They look like stars in the sky and belong to the sea. They come in different colors and sizes. The body has, depending on its type, 5 to 40 arms attached to it. Whoever named them starfish maybe didn't know that they actually walk. If you turn one on its back you can see as many as 15,000 tube feet attached to its arms. Doesn't it sound funny, feet attached to arms of an animal? These feet end in suction pads which are attached to a surface to climb or crawl on.

• They belong with the other marine animals such as Sea Urchins, Sand Dollar and Sea Cucumbers are classified under phylum Echinodermata and class Asteroidea.
• Anyone interested in their anatomy will find that their body plan can be described as a central body and 5 sections arranged around it. The term echinodermata is used for organisms which have spiny skin. The skin on the upper side is made up of calcium carbonate plates. The presence of spine like structures try to protect itself from its enemies. Fish, sea otters, birds and man are its natural enemies.
• They use tube feet to catch their food such as shellfish.
• On an average, a starfish grows to a length of about 8 inches (from tip of one arm to tip of arm on the opposite side of its body). However, some of them have been reported be as big as 3 meters in length.
• It has two stomachs and one of them opens as the mouth in the center of the underside of its body. The mouth can protrude outside and extend to gobble up the food and then passes it to the other stomach which digests it.
• Oysters and clams, worms, sea urchins and crustaceans is their food.
• The starfish use tube feet and other tubes that are present all over their body to breathe in air.
• One of the interesting facts is that most of them have the ability to regenerate arms, in case, they lose one or two in an attack by some predator.
• Each arm tip has some special cells that can detect whether it is light or dark.
• They are found in all the oceans of the world. However, they prefer coastal areas, coral reefs and warm shallow waters.
• A female starfish can lay as many as 2 million eggs. Of these, the number of eggs laid at a time varies between 1-1.3 millions. The egg, when fertilized by the male becomes a larva. This stage in their life cycle lasts for 3 weeks and then it starts changing to assuming its characteristic star shape.
• The most amazing thing about them is that they can change their gender as and when required. If the conditions such as temperature, availability of food, etc., are favorable, a number of male starfish change their gender and lay eggs in an effort increase their population.
• Not all the eggs laid manage to survive. Many of them are eaten by the fish and other marine animals which prevents uncontrollable rise in their population.

Global warming and pollution of the sea water is threatening the habitat of this marine creature. Along with the corals, this fantastic sea animal is losing the battle of survival.