5 Different Types of Jellyfish in Hawaii

Types of Jellyfish In Hawaii
Photo by Tim Mossholder

If you’re planning on vacationing in Hawaii, you may be interested to learn about the types of jellyfish in Hawaii.

The most common jellyfish you’ll encounter will be moon jellies, lion’s mane jellies, and crystal jellies. 

Knowing how to identify these dangerous creatures will help you steer clear of them during your trip and aid in any rescue efforts should you accidentally come into contact with one of them.

Let’s get started on the types of jellyfish in Hawaii.

1. Moon Jellyfish (Aurelia aurita)

Moon Jellyfish is the first on our list of different types of jellyfish in Hawaii, and it is found primarily in shallow, coastal waters. Scientists have studied moon jellies because they are among the largest single-celled animals.

Growing up to three feet wide and weighing up to sixteen pounds, they are sometimes mistaken for giant jellyfish. 

Meanwhile, these jellyfish have no stinging cells or tentacles because their prey is too large and robust for capture. 

Where Might Moon Jellyfish Be Found?

Moon jellyfish are transported by the current as they float at the water’s surface. They can gather in bays, lagoons, or harbors, and you can frequently see them in coastal waters.

As they feed, it’s common to observe them gathered in big groups. Moon jellyfish often wash up on Hawaii’s beaches, especially during storms, giving seabirds a leisurely lunch.

Are moon jellyfish venomous?

No, you won’t get stung by moon jellyfish. Although moon jellyfish contain nematocysts on their tentacles to catch prey, it’s unlikely that coming into contact with one will cause you to feel anything. At most, if you are extremely sensitive, you might experience a mild bee sting.

2. Spotted Jellyfish (Mastigias Papua)

This is one of the types of Jellyfish in Hawaii. The Spotted Jellyfish is an orange-red cube with a diagonal yellow-brown stripe across the middle. It has tentacles, some of which are banded. This species can grow up to 40 cm long. 

In addition, they have a dorsal spine and are capable of stinging if provoked. But they do not seem aggressive and sting people very rarely. 

Furthermore, you can find these at various depths near coral reefs on the reef slope in warmer areas, from the shallows to 10 meters deep around Hawaii or Florida during their winter season from December through March. 

Where Could Spotted Jellyfish Be Found?

Symbiotic algae that use sunlight to produce food are present in the tissues of the spotted jellyfish.

Since they will swim to stay in the best sunlight, spotted jellyfish are typically observed in swarms during the day in shallow water lagoons over sandy bottomed shorelines.

Are Spotted Jellyfish Venomous?

Spotted jellyfish won’t sting you, unfortunately. They no longer have a significant need for stings since they have evolved to rely nearly entirely on sunlight to meet their nutritional needs.

3. Box Jellyfish (Cubozoa)

Box Jellyfish, or cubozoans, have been documented in Hawaiʻi since 1921. They are called box jellyfish because they have long and colorful tentacles resembling decorated gift boxes. 

Though box jellies are found worldwide, these types of Jellyfish in Hawaii prefer warm tropical waters. Box jellies can grow to four feet long and have up to 60 tentacles with stingers on their ends injecting toxins into the host.

Are box jellyfish venomous?

The sting of a box jellyfish is painful, and Fortunately, they are only lethal in scarce instances.

You will immediately feel the sting if you are unlucky enough to come into contact with one of the lengthy tentacles covered in minute stinging cells.

So, when the cells are activated by contact, the jellyfish stings. A barbed thread that the stinging cell can puncture your skin is released.

This caused the jellyfish venom, which instantly burns, to be supplied in a box. Barbs that don’t pierce the skin can stay there and sting you later when you treat the wound.

4. Portuguese Man O’ War (Physalia physalis)

This is one of the most identifiable different types of Jellyfish in Hawaii. Because it’s often extensive and has many tentacles released from the same spot, they are relatively easy to get rid of if you stay out of the water. 

Where Might a Portuguese Man o’ War Be Seen?

On south-facing beaches, where the breezes blow them toward the coast, you can typically find the man o’ war. Inspecting the water before entering is wise no matter where you are during the bluebottle season.

A Man o’ War Stings, right?

The man of war has stinging cells in its tentacles that, when triggered by contact or chemical cues, can penetrate human skin and hurt painfully. 

Multiple stingers frequently linger on the skin’s surface along with the sticky remnants of the tentacle. It’s crucial to use caution when giving first aid so as not to activate these and make the situation worse.

5. Sea Lice (Jellyfish Larvae)

Sea lice are types of jellyfish in Hawaii. Larvae often look like reddish-brown fish eggs. They are usually most prevalent during the spring or early summer months as they peak at this time due to warmer ocean water temperatures. 

Sea lice will latch onto fish or other animals, sucking out their fluids. As well as injecting venom into the victim. 

Also, they can create dangerous water conditions for humans by polluting beaches with decomposed animal carcasses that haven’t been broken down by bacteria yet.

This can make these areas unsafe for swimming and result in illness from consuming sea lice-contaminated seafood, such as oysters, clams, shrimp, or eels.

Can Sea lice sting?

Unfortunately, like other jellies, sea lice can sting and inject toxins. It’s typical to develop a burning rash that might last for many days and be itchy and unpleasant.

This means that many believe swimming while wearing loose-fitting clothing, such as t-shirts, increases the risk of being stung because the sea lice become trapped inside and cause a sting.

Therefore, avoid wearing loose swimwear and use reef-safe sunscreen to protect yourself from bee stings. After swimming, take a quick shower and change out of your bathing suit.

To cure man o’ war and box jellyfish stings, take the following actions:

  1. To lessen venom activity, carefully spritz the region with white vinegar.
  2. Use tweezers, gloves, a plastic bag, a towel, or anything else you have to cover your naked fingers to remove the remaining tentacles carefully. Be careful not to brush or scratch the tentacles, as this can lead to the discharge of more venom.
  3. Use a lot of white vinegar to clean the damaged region thoroughly.
  4. Apply a hot compress or submerge the wound in hot water. Pain reduction may be aided by applying heat.
  5. Keep a close eye on the victim and seek medical help immediately if they experience any breathing problems, such as anaphylactic shock, an irregular heartbeat, altered levels of awareness, or other symptoms of illness.


There are different types of jellyfish in Hawaii, with most being harmless to humans. However, some can be harmful and even fatal if they contact you. 

Therefore this list of the different types of jellyfish in Hawaii should help you avoid any potential danger while on the islands.

The tips come along with information on how to identify them and keep yourself safe from harm during your vacation.

Notify of

Inline Feedbacks
View all comments
You May Also Like