Are Starfish poisonous? Is it OK to pick up a Starfish?

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Are starfish poisonous?

Yes, starfish are poisonous, but all starfish aren’t poisonous. They are not edible for humans in any means, however they do have predators.

Only a few species are venomous to human beings, such as the ‘Crown of thorns’ and a few species of Sun star starfish.

It is also to be noted that starfish do not attack humans, but can inflict painful stings with the release of venom, when they are accidently stepped upon or handled.

Moreover, starfish are not true fishes. They just use the word fish in their name.

There are about 2,000 species of starfish, also called sea stars. Some live in the intertidal zone, while others live in the deepwater of the ocean.

The ‘Crown of thorns’ starfish (Acanthaster planci) is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia).

The crown-of-thorns starfish is one of the largest starfish in the world. It got its name due to the presence of many numerous venomous thorn-like spines covering its upper body surface.

‘Crown of thorns’ starfish (Acanthaster planci)
‘Crown of thorns’ starfish (Acanthaster planci)

Can starfish hurt you?

Yes, starfish can hurt you if you step on them. They are very peaceful and solitary living animals and don’t attack humans.

They normally inhabits the deep ocean floors and so rarely come in contact with humans.

While others, that live in the coral reefs are very small and beautiful looking. Only a few species are venomous like the large ‘Crown of thorns’ starfish (Acanthaster planci).

However, they don’t bite. The only way they can enter the venom is by inflicting painful stings when they are accidentally stepped upon while walking on the coral reef or when handled in a wrong way.

‘Crown of thorns’ starfish has no other mechanism for injecting the toxin, except for the spines that can perforate the tissue of a predator or human, and can inject the venom.

Their venom has saponins along with 15 other different chemicals that give a stinging pain to the inflicted site. This gives a swollen appearance to that stung part of the body.

Along with extreme pain for several hours, persistent bleeding can also occur due to the haemolytic effect of saponins, and nausea and tissue swelling may persist for a week or more.

The spines may be so sharp and brittle, that those may also break off and get embedded deep inside the tissue. Then the spines can only be removed by performing surgery.

Can a starfish kill you?

No, starfish can’t kill you. They don’t have that much of a fatal venom to kill you.

There one sting is just enough to cause extreme level of pain only and not death in adults.

However, if you are talking about kids that are below 4 or 5 years of age, then yes, it can cause death in a few of the cases.

Also the chances of contact with human is extremely low. As, the contact with humans occurs only during deep sea diving, or sometimes when a starfish gets washed ashore.

So, it is mainly the deep sea divers who are at risk.

Now the cases of death occurring due to starfish sting is very low.

The toxicity of the venom entered into the body of the human depends on the severity of signs and symptoms happening after the sting, species type of starfish, the amount of toxin injected in mg, and also it depends on the immue system’s reaction of the human body to the toxin.

It’s always suggested that you reach the medical care unit as soon as possible after you think or know that you have been stung by one venomous one like the Crown of thorn starfish.

The medical treatment would involve the removal of the spines, sanitization of the perforated area and the swollen region of the body, application of antibiotics and painkillers if required.

In general, mid to low venomous stings get well soon within a matter of seven days or so if treated properly. Severe complications leading to death is very very rare.

Is it OK to pick up a starfish?

Yes, it’s OK to pick up a starfish, but you must take adequate care and prevention so that you don’t hurt them or don’t get yourself stung by a venomous one.

It is never suggested that you pick one because if you bring them to the open-air they will die within 3 to 5 minutes due to intoxication.

It’s because starfish breathe using their dermal gills by exchanging dissolved oxygen and carbon dioxide through the skin surface.

But, when they are out in the open air they cannot exchange gases and as a result, they suffer from intoxication, usually with carbon dioxide or monoxide. This causes them to die.

Even without taking them out of the water a lot, the constant handling, taking them out and putting them in the water many times, stacking them, putting them together, or placing them on top of each other as if they were a toy for our creativity, are conditions outside the way of life of these animals, which can also cause them death.

They may also die out of mental stress that is the stress they encounter due to the change in their environment. This can occur even due to the slightest changes in their environment that would lead to heavy stress.

Such mental stress can occur due to rough and wear and tear type handling of the starfish.

It is also to be noted that they are very soft creatures and are born with intricate and fragile arms and tiny body structures.

In spite of its regeneration capabilities, even the slightest poke may hurt or damage them, most especially when people carelessly throw them out of the water. Thus, leading them to death.

Also, do make sure that you wear a pair of gloves before you put your hands on any of the starfish that you find near the shore.

If you would have applied the sunscreen or anything on your hands than catching them barehanded can cause them to die because of the acidic pH of the sunscreen you may have applied. So, it’s suggested that you wear gloves beforehand or else don’t catch one.

Are starfish aggressive?

Yes, starfish are aggressive, but for their prey species, not for humans. They are not aggressive in the same sense as fish can be. They are slow-moving and basically defenseless.

They are so aggressive towards their prey like the shellfish that some can eject their stomachs out of their body to capture their prey.

Using pressure exerted by the water vascular system, the cardiac stomach can be pushed outside of the sea star’s body and can be inserted inside a shellfish.

They can then insert their stomach inside the shell of the starfish and bring them out of the shell and then into their stomach.

They have eyes that give them the ability to navigate and set up their natural attack behaviour. And, the eyes are located in a pretty weird place that is on the tips of their arms.

Non-aggressive starfish feed on algae and planktons where they don’t need to hunt for their living prey.

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