How Dangerous is a Moon Jellyfish Sting?

To begin with, does a Moon Jellyfish sting dangerous?

Not really; they are mostly harmless. Are their stings lethal? No, they mainly cause irritations and only are severe if the sting is caused by bloom.

Moon jellyfish are often the species most aquariums house and are available as pets in home aquariums. They are usually sold and housed because they are mostly harmless and quickly adapt to extreme environments.

Most of us would have visited aquariums as a child. The Jellyfishes would have stood out with their ethereal beauty and unearthly appearance with their structure and bioluminescence.

Whether or not we are interested in animals, the more we learn about jellyfish, the more fascinating and bizarre they seem.

Nature of Jellyfishes

A jellyfish
Photo by Connor Wang on Unsplash

Most biologists and Marine biologists use the term Cnidaria Medusozoa 1for the Jellyfish or Sea jellies as we call them. The jellyfish that we recognize in general are in the Medusa phase of their reproductive life cycle.

This is when they are either male or female and produce a larva dispersed onto the seabed, where polyps plant themselves and grow until they can grow further. Then they either continue to their next life cycle or age backwards (like the immortal jellyfish Turritopsis dohrnii) to their younger selves and repeat the cycle.

Jellyfish can be found worldwide today, with the changing climatic conditions and their rapid breeding. Jellies are one of the oldest animal groups that have existed for more than 500 million years but have a short life span stretching from 6 months to 3 years.

Some immortal jellyfish species can live on for centuries, reproducing asexually and through reverse ageing. They are also used in research to understand their mysterious natures, bioluminescence, and evolving nature.

Sting of Jellyfish

Their interactions with human life can be mild to hostile. Thousands of swimmers get stung by them, with the sting’s effects ranging from slight irritations to death.

Box Jellyfishes are often the reason for these deaths, with Lion’s Mane jellyfish being the second one.

With favourable environmental conditions, Jellyfishes form swarms or blooms that can cause many problems, like damaging fishing gear, clogging cooling systems in power plants, stinging underwater swimmers, and affecting tourism in places with beaches.

Jellyfish often survive in warmer waters, and climate change due to global warming contributes to their growing numbers and interactions.

Jellyfish often don’t intentionally sting humans, as we are neither prey nor predators. When we brush against them or come into contact accidentally, their sting cells are activated, or they release a mucous which affects us depending on various factors.

The mild stings can be immediately helped by taking out the sting and pouring or dipping the body part in vinegar and a mixture of baking soda and sea salt.

Harvesting of Jellyfishes

Jellyfish are harvested in many Asian cultures and consumed as a delicacy. They aren’t rich in any particular protein but are gelatinous. They are also harvested for their aesthetic beauty, venomous properties, and collagen.

Jellyfish move using their tentacles and through moving their entire body, which is saucer-shaped.

How do Jellyfish Breathe?

Jellyfish are very basic creatures that do not have digestive, respiratory, or circulatory systems. They mostly breathe using the diffused oxygen in the sea or freshwater and excrete food and other wastes by creating voids.

They are primarily carnivorous and consume small plankton2, other small sea creatures, and sometimes birds near the water surface.

How are Moon Jellies different from other Jellyfishes?

Facts: The Moon Jellyfish

Moon jellyfish is one of the most common jellyfish that we have likely seen or will interact with within the world’s oceans. These creatures are generally harmless, but their blooms have been causing problems in many parts of border European-Gulf countries, Florida, and the Mexican Caribbean centre.

These creatures are nearly invisible with their transparent bodies and glow an unearthly blue in the darkness under the ocean’s surface. Aquariums often place them on blue backgrounds to quickly see their natural beauty and luminescence.

They are called Aurelia Aurita, belonging to the Aurelia species. They are easily recognized by their transparent saucer-like bodies and highlighted pink-purple petal-like organs under the skin, which are their reproductive organs.

Unlike other jellyfish, the Moon jellies do not have long tentacles. Because of this, they are weak swimmers and primarily depend on ocean currents and tidal movements for moving and large travel.

Moon Jellyfish and Their Nature

This species is especially well-known due to its worldwide presence and the growing number of its bloom, which is beautiful but causes numerous problems. While they tend to get washed up on beaches, they can also be seen when people visit scuba dive or swim underwater to see sea life.

While they are primarily dead when washed up on-site due to dehydration, their stingers are still functional and sting in defence if touched. Their stinging cells mostly release natural toxins, which are venomous, and pre-dominantly affect our skin and blood.

In addition, as mentioned before, they are harvested and bred to be sold and displayed in private and public aquariums.

They primarily consume plankton, molluscs, crustaceans (crabs and shrimps), larvae, protozoans, eggs of other creatures, fish eggs, and other gelatinous zooplankton3. They lack respiratory or digestive systems, much like other species, and survive on diffused oxygen in the water and diffuse nutrients to their cells.

The moon jellyfish stings are not lethal, not even to their predators, and only cause an irritating sting that makes them leave the moon jellyfish alone. They are preyed upon by fish, sea birds, and sea turtles.

As they have very little nutritional value, a predator might consume large amounts of them to maintain the required energy levels.

Nature Notes: Moon Jellies

They have also recognized microbeads in cosmetic and personal care products and avoid them because they are not food, unlike most other sea creatures. They have a rough life span of six months that could stretch slightly over a year if kept in a protected and harvested human-cared environment.

Regular beach-goers and scuba divers have higher chances of coming in contact with a moon jelly or a bloom of these jellyfish. They are not predatory by nature and are basic surviving creatures with minimal working systems. Hence they will neither intentionally attack nor follow you if you avoid them altogether.

The effect of their stinger mainly depends on the person’s health, physical structure, pain tolerance, and skin conditions.

The moon jellyfish’s sting especially causes:

  • Rashes
  • Irritations
  • Red welts on the skin with itching
  • Sometimes only significant envenomation on the human cells causes a stinging sensation.

The effects stay for two weeks and can completely heal in a week with the right medicine and care.

What to Do if you Get Stung by a Moon jellyfish?

Do moon Jellyfish sting?

Most of the time, when a moon jellyfish stings, there is no need for medical care, and it can be helped with self-treatment to the affected area using home remedies like baking soda.

Steps to take if stung by one or more moon jellyfishes are:

  • Remove the sting (if attached to you) using pliers or the edge of a card.
  • Rinse the surface thoroughly with saltwater or seawater and baking soda. Washing it with minerals or freshwater will only aggravate the skin and the sting, so please avoid it.
  • Rinse or pour vinegar on the skin, as it will calm the reaction and the burn of the sting.
  • Try not to scratch or irritate the treated skin further.
  • Treat the discomfort with hydrocortisone cream or lotion to reduce pain and inflammation.
  • Taking antihistamines would help reduce the itching sensation, like Calamine lotion.
  • Avoid urinating on the sting, as it can aggravate the skin and lead to more venom release, which undoubtedly does not help with how unhygienic it is.

These steps are the basics of dealing with the sting of a moon jellyfish’s stinging tentacles, provided it is a typical circumstance.

In an occurrence where the victim is a child or has sensitive skin or health conditions, or the sting was to the face or mouth or genital, immediate medical care will be required and is highly advised.

How to Avoid Being Stung by Moon Jelly?

  • Avoiding the bunch of jellies swimming in water is a simple but effective step.
  • Wearing a protective suit and footwear in addition also helps. This prevents the stings from getting attached to the skin itself.
  • Know in advance about the possible interactions that could happen during any circumstances, and remain updated on dealing with areas prone to jellies.
  • Try not to pick up gelatinous blobs that have washed up on sandy beaches or shore that could be the moon jellyfish or a considerably harmful species of jellyfish.

Key Takeaways

Moon Jellyfish
Photo by Alicia Quan on Unsplash

In conclusion, Moon Jellyfishes belong to a category of aquatic animals that are essentially harmless and only problematic when large in numbers.

So, we can say that moon jellyfish stings are not that dangerous to humans as these jellyfish do not have enough strength in their stings to push through the human skin.

Like the quote, “Prevention is better than cure,” avoiding a situation of getting stung from them and enjoying your beach or water experience is the way to go.

Read more from us here.


1. Is it safe to touch moon jellyfish?

Ans. The sting of jellyfish is not easily penetrative into human skin and thus it can be touched safely.

2. Are moon jellyfish rare?

Ans. Not really. Moon jellyfish are not endangered.

3. Which is the most dangerous jellyfish?

Ans. Australian box jellyfish are the most dangerous jellyfish.

A Guide To Spider Bites Symptoms & Diagnosis
Icy Health
  1. Kherchouche, Aldjia, and Aziz Hafferssas. “Species composition and distribution of Medusae (Cnidaria: medusozoa) in the Algerian coast between 2° e and 7° e (SW Mediterranean Sea).” Mediterranean Marine Science 21.1 (2020): 52-61. ↩︎
  2. Irisson, Jean-Olivier, et al. “Machine learning for the study of plankton and marine snow from images.” Annual Review of Marine Science 14 (2022): 277-301. ↩︎
  3. Pierson, James, et al. “Mesozooplankton and gelatinous zooplankton in the face of environmental stressors.” Coastal Ecosystems in Transition: A Comparative Analysis of the Northern Adriatic and Chesapeake Bay (2020): 105-127. ↩︎

Last Updated on by Suchi


Apeksha soni

Leave a Reply

Your email address will not be published. Required fields are marked *