How do Jellyfish die? What happens when a Jellyfish dies?
Do Jellyfish die? Are there immortal Jellyfish?
Yes, Jellyfish soon dies after they have completed their life cycle. Some species of the Jellyfish soon dies after mating or after fertilizing the egg and releasing the embryo out of the body of the female.
For example, Some species of Aurelia Jellyfish have a natural life span of not more than 6 to 8 months. They do naturally die after living and reproducing for several months in the marine water.
Although some specimens that are properly cared for in public aquarium exhibits typically live several to many years. But, they do die.
For example, many colorful Jellyfish species that are common in the coastal zones worldwide complete their life cycle within a year or so. The medusa of most species is fast-growing, and they rapidly mature within a few months and die soon after breeding.
Some species of Box jellyfish that shows mating ritual do not have long lives. They may spend less than a year in the medusa form and only a few months as a polyp. And, this entire cycle can take place over the course of two years or less.
Jellyfish can also die out of water. As soon as the jellyfish are washed up on the sea-shore by the retreating tide, the jellyfish begins to die.
Jellyfish are 95% made of water, and so when in the water a jellyfish breathes by taking in oxygen from the seawater through their transparent skin. And so, as soon as it is on dry land, it dries as it can no longer breathe and live outside of water.
Another reason is that they’re cold-blooded animals and can lose mobility when water temperatures are below normal. So, if the water temperatures are excessively below normal for a longer period of time they will die.
So, Are there immortal Jellyfish? To date, marine biologists have well-discovered only one species named Turritopsis dohrnii (also called immortal Jellyfish). This is the only species of ‘biologically immortal’ jellyfish discovered so far.
Turritopsis dohrnii never die because they transform themselves back into their juvenile polyp stage which is long-lived, and this transformation cycle happens again and again. And, so they are biologically immortal.
How do Jellyfish die?
Jellyfish like the Flower hat jellyfish that lives in the Western Pacific, and many other colorful Jellyfish species that are common in the coastal zones worldwide have their life span of not more than 1 year or so. They complete their life cycle within a year or so.
Some species of jellyfish like Aurelia aurita (Moon Jellyfish) shows fast development of the Planula larva to the mature Medusa stage. In just a few weeks, Jellyfish larva become mature and gets ready to start the next reproduction cycle. After this they do die.
Some species of Box jellyfish like the Copula sivickisi shows advanced mating ritual and courtship dance when the male is about to internally fertilize the female. And so soon after that, they lay the under-developed eggs and then they die within two to three days. Their life span is just two years or more.
Individual jellyfish can also die due to predation that when they are eaten alive by animals like tunas, sharks, swordfish, sea turtles, and penguins.
They can also die due to the various diseases that happens in the medusa stage or even during the other stages of the life cycle.
Jellyfish can also die if thrown out of the water into the sea-shore by the retreating tide. They can’t breathe out of the water so the jellyfish soon begins to die.
Some of the Jellyfish species like the Cannonball jellyfish (Stomolophus meleagris) and a majority of other jellyfish species tend to travel and migrate in groups, called blooms. And as such, if the water temperature during the migration gets cooler than normal then they die because they are cold-blooded animals.
What happens when a Jellyfish dies?
During the medusa stage of the Jellyfish, which is when the adult Jellyfish dies, it sinks to the ocean floor and begins to decay. Soon after that, the decomposers like fungi, marine worms, echinoderms, crustaceans, and molluscs start to decompose that dead remain.
If you see any other dead jellyfish being washed up and lying dead on the beach or sea-shore than, you probably need not require to do anything.
Nature will take care of removing those dead organisms lying in the beach or sea-shore as they will be eaten by seagulls, crabs, and other scavengers.
If you are in the ocean bed, you can’t smell the bad rotten smell of the dead Jellyfish.
But, if you are nearby a dead Jellyfish lying on the shore then it can be a disturbing and kind of disgusting sight. And also, the smell leaves a lot to be desired, as well.
If a jellyfish is dead, you will find that the jellyfish has lost its typical round shape of the umbrella body and is sort of flat. This type of flat body shaped dead ones can be seen both in water and in the sea-shore, most probably lying in the shore, if the jellyfish is dead.
Also keep in mind that a dead Jellyfish can also sting. The scenario may be that you go near to an alive Jellyfish expecting it’s dead.
Or, if the jellyfish is dead then it can still sting you as the Stinging cells (nematocysts) are triggered and get stimulated by touch whether the jellyfish is dead or alive.
Is it safe to touch a dead Jellyfish? Can Jellyfish kill you?
No, it’s not at all safe to touch a dead Jellyfish, even if it’s dead. You can get stung if you step on a Jellyfish, even a dead one.
Jellyfish have thousands of tiny stinging cells (also called nematocysts) attached to each of their tentacles. These stingers can continue to release jellyfish venom (poison) into the body once they get triggered on touch by external means.
The venom of Jellyfish that comes out of the nematocysts contains hemolytic, neurotoxic, and cardiotoxic venom. Additional toxins may also cause massive dermal necrosis.
The dosage of toxicity in the venom highly depends on the species type of Jellyfish.
So, let it be a dead or an alive Jellyfish, the triggering mechanism of the nematocysts always remains ON and active unless and until the organism is complete eaten by predator or is being fully decomposed.
So, better not to touch and play with a dead Jellyfish, if you don’t know whether it is venomous or not.
So, Is it safe to touch a dead Jellyfish? No, it’s not safe to touch a dead Jellyfish but, it’s always safe to better stay away and get rid of such venomous organisms.
So, Can Jellyfish kill you? No, not all Jellyfish species can kill you. Some are very venomous, some are mildly venomous, and only a few species are non-venomous at all.
The very venomous one’s sting can be extremely painful and can also lead to death in humans. The mildly toxic ones can make you fall ill with an extreme level of pain.
The non-venomous ones are the safest ones but don’t go near to them if you can’t recognize it.
For example:
- Box Jellyfish (Chironex fleckeri) is one of the most venomous ones that can lead to death if not treated ASAP.
- Moon Jelly (Aurelia Aurita) is one of the mildly venomous Jellyfish species known to man.
- A few of the species of Cannonball jellyfish are considered non-venomous as they contain an ignorable dosage of venom for humans to even feel the pain.
Can Jellyfish regenerate and clone themselves?
Yes, a majority of the Jellyfish species known so far can clone and can regenerate their body parts all by themselves.
Mainly if you follow their life cycle, you will find that when they are in their Polyp stage, they can asexually create several clones of themselves. These clones can then grow into individual sexually mature adult Jellyfish reaching the Medusa stage.
This type of cloning is seen so well because Jellyfish do have a combination of sexual and asexual reproduction processes during their life cycle.
Some species of Jellyfish can even regenerate their lost body parts when they are in their adult medusa stage. It can be seen when they have lost a part of their body.
In the section of their lost body part, the tissues grow back perfectly and seal up to heal that section completely. They just don’t perform regeneration, they can do extreme regeneration leading to even immortality in a few of the species.
Not only regeneration, but Scientists also have suggested that the free-swimming adult jellyfish of the Medusa stage possess actively proliferating cells that play a key role in controlling body-size, and tentacle shape as well.
Turritopsis dohrnii is an immortal Jellyfish. Is this true?
Yes, this is very true. Turritopsis dohrnii is an immortal Jellyfish species well-discovered so far. This jellyfish is commonly known as immortal jellyfish.
They are found worldwide in temperate to tropical waters.
Other immortal species that include the jellyfish Laodicea undulata and species of the genus Aurelia are also immortal. But, these species are not well-studied so far.
They don’t die because they transform themselves back into their juvenile polyp stage which is long-lived.
When they transform themselves from their adult medusa stage to the juvenile polyp stage their tentacles retract, and their bodies shrink, and they sink to the ocean floor and start the cycle all over again.
That’s why Turritopsis dohrnii is immortal.
Their fertilization process is external that is both male and female gametes fuse in the open water out of the body of the female.
It has also been seen that most jellyfish species have a relatively fixed life-span, which varies by species from hours to many months.
The medusa of Turritopsis dohrnii is the only form known to have developed the ability to return to a polyp state, by a specific transformation process that requires the presence of certain cell types (tissue from both the jellyfish bell surface and the circulatory canal system), making them immortal.
Experiments have revealed that all stages of the medusae, from newly released to fully mature individuals, can transform back into polyps under the conditions of starvation, sudden temperature change, reduction of salinity and artificial damage of the bell with forceps or scissors
