Hawaiʻi’s beautiful beaches aren’t always so tranquil. Oʻahu attracts thousands of beach goers each year, but some areas can also be home to a dangerous creature: the stinging box jellyfish.
The Box Jellyfish is one of the most dangerous creatures living in Hawaii. Found in tropical and subtropical waters around the world, these stingers inhabit almost all of Oʻahu’s Northern Windward coast during certain times of the year and can cause severe pain and injury if a person is stung by one.
Here is a comprehensive guide about box jellyfish on Oʻahu beaches, including how to spot them and what to do if you get stung.
What Do They Look Like?
Box jellyfish have an oval-shaped bell with four clusters of tentacles extending down at angles. Their bodies are transparent, but may have faint whitish streaks throughout their body and tentacles.
Depending on species and size, they range from 0.5 cm—25 cm wide and up to 60 cm tall, with symbiotic algae living inside their tissues for plankton capturing purposes.
Furthermore, the jellyfish has two rings of up to 16 eyes, which assist it in identifying potential prey items or determine when it should swim away from danger.
How Did They Get To Oʻahu?
The box jellyfish likely came from other Pacific islands such as Tahiti or even Australia due to strong ocean currents that cross vast distances.
While their exact origin is unknown, it’s believed that the population was introduced to Hawaii many years ago and has been slowly growing ever since.
Where Can You Find Them?
The box jellyfish is found primarily off Hawaiʻi’s south shore beaches including Kailua Beach Park (Kite Beach), Ko Olina Lagoon 4 and 5, Waimea Bay and Māhukona Beach Park on the Big Island.
Generally speaking, it favors shallow waters with low wave activity near the beach break line or deeper into lagoons. They often congregate in large numbers near river mouths or areas where freshwater meets saltwater.
You may also find them drifting in long-shore currents along beaches they inhabit; they tend not to venture far from their warm water “comfort zone” but can stray if there’s enough food—namely planktonic organisms—available elsewhere in the ocean.
When Are They Active?
The months when the stinging box jellyfish is most prevalent on beaches in Oʻahu range annually from April to September, but warm temperatures are likely to cause a greater focus of them from May until July.
Recreators of the seas – swimmers, surfers and marine fans – should be mindful during those months as many places in the ocean may result in more of these critters occurring at certain parts of Oʻahu’s coast.
The list comprises north shore (Waimea) and south shore spots (including Ala Moana, Waikīkī, and Hanauma Bay) however you should keep in mind that these jellyfish may appear on other occasions and beaches such as leeward (western) shores and windward (eastern).
It is therefore essential to check up on local information whenever going into the water during these periods or whenever visiting any beach.
What Causes Invasions?
Box jellyfish invasions have become a growing problem in recent years, and researchers at the University of Hawaii Manoa have been trying to understand why.
After conducting a study over 10 years, they discovered that the number of hours between sunset and moonrise is key to triggering jellyfish migrations.
This phenomenon occurs on a monthly basis, with the same number of hours of darkness during each lunar cycle causing jellyfish to come ashore.
The findings from this study suggest that box jellyfish invasions are not random occurrences, but rather are triggered by specific environmental conditions. This means that it is possible to predict when these invasions will occur and take steps to mitigate their impact.
For example, beach goers can be warned ahead of time if an invasion is expected, so they can take precautions such as wearing protective clothing or avoiding swimming in affected areas.
Understanding what causes box jellyfish invasions could help us better protect our beaches and coastal communities from their effects.
What Should You Do If You’re stung?
If you see one or more jellyfish swimming gracefully in front of you while swimming at the beach or simply playing in the shoreline shallows — get out immediately!
Despite their look of elegance, these creatures possess powerful stingers that can cause excruciating pain upon contact with skin tissue — much more than other varieties such as moon jellies or sea nettles often seen around harbors on both coasts of America.
And once touched—unless severe redness persists for days afterward—it’s best practice only to rinse off affected areas thoroughly with warm seawater (not fresh!) until pain subsides slightly.
It is important to know what to do if you are ever stung by a box jellyfish. A short YouTube video from KHON2 News in Honolulu provides helpful information about how to treat a jellyfish sting.
The video recommends rinsing the area with vinegar for 30 seconds and then immersing the affected area in hot water (as hot as can be tolerated) for 20 minutes.
It also suggests taking an antihistamine such as Benadryl and seeking medical attention if necessary. By following these steps, you can help reduce the pain and discomfort associated with a jellyfish sting.
What NOT To Do If Stung
When it comes to treating jellyfish stings, there are certain methods that should be avoided. Seawater or salt water, soda beverages, urine, and any kind of alcohol such as vodka, rubbing alcohol or isopropyl have all been found to be ineffective but will not make the stinging worse.
Do not use ice directly applied onto skin as it worsens inflammation and burning sensation due to cold temperature shock as well as depriving necessary oxygen cells/blood away from reaching the wound site.
This would slow healing time & leave an unhealthy permanent dead skin trace after healed due to extreme damage.
Lastly, remember to seek professional medical help right away if discomfort & swelling last a long time without relief or if a mild-moderate rash appears.
These could be signs pointing towards symptoms beyond typical allergic reactions associated with a Box Jellyfish encounter showing up afterwards which suggests life-threatening complications developing requiring immediate medical assistance.
How To Avoid Getting Stung
The best way to avoid being stung by box jellyfish is to stay out of the ocean during times when they are known to be present – late Spring through early Fall on O`ahu’s North Shore line.
You may also want to look into protective clothing or lycra suits that can provide protection against their powerful stinger cells while swimming in areas where they live regularly like Pearl Harbor or Kaneohe Bay throughout the year round.
Be sure to not only check your local beach report but also watch for warning signs placed by lifeguards along shorelines before entering the water and be sure to wear protective gear when possible.
Before entering any body of water off Oʻahu beaches, it’s important to make sure that conditions are safe for swimming.
Avoid swimming at night when box jellyfishes hunt actively near shorelines or after rainfall due to increased salinity level from freshwater runoff that allows them to cruise closer inshore.
Watch Out For Warnings
When visiting Oahu beaches, be aware that a red warning flag indicates the presence of dangerous marine life onshore. While this can refer to jellyfish or sea lice—microscopic larvae that cause skin irritation—a red flag will be displayed in either case.
Enjoying The Beauty Of The Jellyfish
The beauty of Hawaii is best experienced through its vibrant marine life, and Hot Island Glass offers a unique way to appreciate it.
Located in Maui’s small paniolo town of Makawao, visitors can watch live glassblowing demonstrations 9-5 each day and purchase stunning jellyfish glass art.
The intricate sculptures are made with the utmost attention to detail, capturing the graceful movements of these majestic creatures.
The glassblowers use a variety of techniques to create their pieces, from blowing and shaping the molten glass to adding color and texture with enamels or paints.
For those who can’t make it out to Makawao, Hot Island Glass also offers online shopping for their beautiful jellyfish sculptures.
These pieces make great gifts or home decor items that will remind you of your time in Hawaii every time you look at them. Whether you’re looking for something special for yourself or someone else, Hot Island Glass has something for everyone!
In Summary
The box jellyfish is a dangerous creature that can be found on Oʻahu beaches during certain times of the year.
To avoid being stung, it’s important to stay out of the ocean during these times and to wear protective clothing when swimming in areas where they are known to live.
It’s also essential to watch for warning signs placed by lifeguards and to check local beach reports before entering any body of water. By following these tips, you can ensure a safe and enjoyable experience while visiting Oʻahu beaches.
Hi, my name is Richard Ennis and I have been to Hawaii eleven times so far. I have always been fascinated with the world of Hawaii, ever since I was a young boy learning about it in school.
So, please enjoy my website and marvel at the state of Hawaii - if I convince you to plan your own trip out there, hope to see you soon!
