With around 2,000 species worldwide, starfish are fascinating creatures that leave many people wondering, what do starfish eat and how do they eat?
First of all, starfish come in a range of shapes, sizes, and colors and can be found in the Arctic, Antarctic, and many other oceans around the world with the most diverse number being in the Pacific region.
These fascinating creatures have no bones or brains and they regenerate themselves, eat, and move much differently to other aquatic animals.
In this article we are going to look at what starfish eat in the ocean, the aquarium, and starfish species specific diets.
Starfish Overview
Starfish are from a group of animals called Echinoderms where there are around 7,000 species. Some of these species include sand dollars, crinoids, sea urchins, brittle star, and sea cucumbers.
Animals within the phylum Echinodermata have many characteristics such as a flat body, tube feet, an absent head, and symmetrical limbs around a single centre point known as radial symmetry.
Although they are well known as starfish, they are also known as sea star with many experts around the world calling for this complete name change. The reason behind this is because the may live in the water, but they have no similarities to fish.
Not only do they move around using tiny tube feet, they also have no gills, fins, or scales, and sea water is used by their bodies to help circulate nutrients instead of blood.
Starfish can weigh up to 11lbs and grow between 4.7 – 9.4 inches depending on the species. Their lifespan is anywhere between 5 and 35 years.
How do Starfish Eat?
You may be wondering, how do starfish eat? They have one of the most fascinating forms of feeding in all of the natural world and you will be truly amazed.
As starfish do not have visible mouths, it took scientists a while to discover the process in which starfish eat. Scientists released a brief in 2013 based upon their remarkable discovery.
They found that the stomach of the starfish extends out of it’s mouth covering the digestible soft parts of their prey. These feeding process creates a soup-like substance which retracts back into their bodies. They also have a second stomach that stays inside of the body.
A neuropeptide is responsible for this feeding feat which is a signal carried by a molecule between neurons called NGFFYamide. The most interesting part is that scientists say that it may be a possibility to alter starfish feeding habits in the future.
Check out the amazing video below of a starfish feeding.
Do Starfish Have Teeth?
As stated previously, starfish do not have teeth as they have a unique way of eating using one of their two stomachs which extends from their mouth and wraps around their prey.
When Do Starfish Eat?
Starfish are typically nocturnal which means they eat at night, although you can adapt them to feed during the day if you need them to feed in this way.
How Often Do Starfish Eat?
Starfish should be given food roughly every two to three days. If you place food near the starfish and they eat it immediately, this is a sign that they are hungry.
What Kind Of Food Does A Starfish Eat?
What Do Starfish Eat In The Ocean?
Their diet and what they eat is going to depend on the species of starfish. Some are similar to fish, some are predators, and others are scavengers. Most of them are carnivorous predators who feed on clams, mollusks, and oysters.
Here’s a full list of things that a starfish would eat in the ocean.
- Clams
- Mussels
- Oysters
- Barnacles
- Hermit crabs
- Decomposed organic material
- Coral polyps
- Planktons
- Other starfish
- Sea snails
- Seaweed
- Sea urchins
- Slow-moving fish
- Algae
- Shrimp
- Squid
- Sponges
- Sea cucumbers
- Tubeworms
- Anemones
- Chitons
- Hydroids
- Fish eggs
- Sand dollars
- Other crustaceans
- Gastropods
- Bacteria
A single starfish can eat over 50 clams in a single week in the ocean.
What Do Starfish Eat In Aquariums?
It’s important to make you aware that starfish require a lot of care and attention, along with a large tank of at least 100 gallons. So as beautiful as they are, they are probably best avoided if you are a beginner.
Starfish can be grazers which means they will feed off things that have fallen to the bottom of the tank such as pellets and fish flakes, although they cannot just be fed fish flakes alone.
Here are some of the common things various species of starfish will eat in an aquarium.
- Mollusks
- Algae
- Shrimps
- Prawns
- Sponges (not frozen ones)
Some species will eat kale, boiled spinach and other green vegetables and some will even eat corals.
Starfish Species Specific Diets
- Chocolate Chip Starfish: Shrimp, squid, sponges, chopped clams, tubeworms, and soft corals.
- Crown Of Thorn Starfish: Stony corals like staghorn corals.
- Marble Sea Star: Detritus, micro-organisms, shrimp, flaked food.
- Sand-Sifting Starfish: Shrimp, mollusks, urchins, plus extra supplementation.
- Linckia Starfish: Clam meat
- Pacific Blood Starfish: Sponges, bacteria, planktons.
- Leather Starfish: Sponges, cucumbers, chitons, anemones, fish eggs, hydroids, and sea urchins.
- Sunflower Star: Sand dollars, clams, sea cucumbers, sea urchins, crustaceans, fish, and gastropods.
- Egyptian Sea Star: Alae, sponges, and snails.
Common Starfish Diet Questions
Do Starfish Eat Algae?
As you can see in the previous section, some species of starfish such as the Egyptian Sea Star eat algae.
Do Starfish Eat Snails?
Some species such as the Egyptian Sea Star eat snails.
Will Starfish Eat Your Pet Fish And Coral
Some species such as the Crown Of Thorn Starfish will eat corals as part of their diet. Other species of starfish are perfectly fine to keep in your tank without the worry of them eating your fish and coral.
Before purchasing starfish, it’s very important to do your research and make sure you are getting the correct species for your aquarium.
Do Fish Eat Starfish
Most starfish are safe from other fish due to their calcified bony skin which acts as a protection.
Conclusion
Starfish are fascinating creatures who would make a great addition to your aquarium because of their beauty. Just always remember that they are not idea for beginners because they require a lot of care and attention.
