What Do Brittle Stars Eat?

Have you ever wondered what do brittle stars eat? These multiarmed close relatives to starfish have evolved to live at the bottom of the seas, and more than half of their species can be found at depths greater than 600 feet. Most of their species scavenge the sea bottoms feeding on decomposing organic matter produced by animals and plants living above them.

They have a mouth on the underside of their “belly” which is surrounded usually by jaws. Their mouths serve them bot as the start of their digestive system, for ingesting the food, and also as the end of it, for egesting the undigested material. Some brittle star species even use their arms to catch bacteria and plankton carried by currents around them.

What do you feed brittle starfish?

Because they are scavengers, if kept in aquarium brittle starfish will feed on leftovers and clean the aquarium of detritus created by other fish. But if they don’t have enough companions to provide with enough to eat, you will need to give them additional food. Most of the brittle star species are not picky eaters, they are omnivorous. They will eat both marine plants and marine animal-based food.

If you overfeed them, they will create a stash of decomposing food, which is a delicacy for them.

Do brittle stars eat coral?

In general, brittle stars will not eat corals, and just leave them be. Some species, that are big enough, will feed on dead or dying shrimps and other small crustaceans in absence of other food. If you notice that your brittle stars are eating soft coral it may mean that you have two problems with your aquarium.

Very likely your brittle stars are underfed, and actively looking for the additional food source. But they will not feed on healthy coral. This means that there could be some health problems with your corals because brittle stars will eat dead and decaying pieces of them.

How do brittle stars survive?

Because they are bottom dwellers, to survive and protect themselves from predators they bury in the seabed or hide in nooks and crevices they may find. Often they will leave just one of their arms exposed in search of a quick bite that currents may bring them. Though a part of their body is exposed to predators, they have another mechanism that helps them survive attacks from predators.

Brittle stars are named so because their limbs very easily break off if tugged. In some unfortunate event for them, a hungry fish searching for food can attack their exposed arm. But brittle stars have a very strong regenerative ability and will grow back the missing appendages.

Do brittle stars eat phytoplankton?

Some brittle star species in the wild rhythmically wave one of their arms and thus catch detritus, phytoplanktons, and zooplanktons if they are present in the water sorrrounding them. They are omnivorous scavengers which means that they will eat almost any decomposing organic material, that includes the dead or dying phytoplanktons.

Phytoplanktons are mostly found in well-lit shallow sea waters, while brittle stars are usually found in greater depths. Because of that in the wild, they will eat only dead plankton and bacteria that fall on the sea bed. In the aquariums, brittle stars will eat phytoplanktons because it is easier to catch.

Can brittle starfish kill fish?

Though they are preferably scavengers and also feed on detritus, some larger species do hunt and prey on other sea creatures. Mostly those are smaller sea animals, like small crustaceans and mollusks. Brittle fish are nocturnal animals and larger ones may attack shrimps, squids, and smaller fish when they are sleeping or are sick and dying.

Can you touch a brittle starfish?

Brittle stars are safe for touching, but touching them may not be safe for them. Just like their starfish cousins, brittle stars can’t “hold” their breath longer than 30 seconds. Picked out of water will be in danger of dying prematurely.

Another thing why you shouldn’t be picking up brittle stars with your hands is connected with the reason of the name. They are somewhat brittle.

With relative ease, you could accidentally pull off one of their arms. Another problem is that if they sense the danger they can intentionally throw off one of their arms in an effort to escape. They will regrow it after some time, but like with any other living creature, it’s better to avoid hurting them in the first place.

Do brittle stars bite?

While brittle stars have mouths surrounded by five jaws, and larger species of them may attack smaller sea creatures, they do not bite. In that sense, you are very safe from them. If you handle them you present a much bigger danger for them as you can easily injure them.

Are brittle stars poisonous?

Brittle stars are neither poisonous nor venomous. They do not produce any kind of venom, and also do not have any mechanism of delivering it to their potential “victims”. Some larger species have a type of blunt spikes that serve some other purpose.

Although almost all of them have tiny tubes bristling their arms, those are the feeding tubes. These they use to pick nutritious material that surrounds them and bring it closer to their mouths.

While they are not poisonous they are neither really edible. They have a very strong skeletal system consisting of the calcium mineral calcite, because of which they can’t be used as food.

Why are brittle stars important?

Brittle stars are scavengers and feed on detritus. They are very important members of ecosystems. Just like all scavengers that can be found in nature, they are important for keeping the ecosystem healthy and thriving. Dead animals and plants and other decomposing organic material is always the source of pollution and can be a source of many illnesses that can spread among other members of the ecosystem.

In the arctic ecosystems, they are also an important food source for some fish, crabs, and starfish species. In the home aquarium, they are a species that will help maintain your aquarium healthy and clean.

References:

• Brittle stars Subclass Ophiuroidea http://www.wildsingapore.com/wildfacts/echinodermata/ophiuroidea/ophiuroidea.htm
• Brittle Stars https://www.aboutfishonline.com/articles/brittle-stars.html
• Arctic Wildlife: Get to Know Brittle Stars, Ocean Conservancy https://oceanconservancy.org/blog/2016/03/30/arctic-wildlife-get-to-know-brittle-stars
• Brittle star https://en.wikipedia.org/wiki/Brittle_star