Every month the Box Jellyfish arrive about a week after the full moon. The Leeward part of Oahu is most commonly affected. The jellyfish can be found for about three days during this time. You’ll usually see them around Hanauma Bay, Waikiki Beach, Ala Moana Beach Park, and sometimes as far as the Wai`anae Coast. These are not the deadly type, the Sea Wasp. The Sea Wasp is found in Australia, not Hawaii.
Because they are transparent, the box jellyfish are very hard to spot. They have square bodies and are about 2 0r 3 inches tall, with tentacles as long as two feet. It is good to walk the coastline and check for signs of the jellyfish washed up on the beach. Or if someone else on the beach has been stung, stay out of the water. Also check for posted signs.
Box jellyfish are found to sting more often in the AM hours when they are nearer to the surface. You may not even see the sting but experience symptoms such as: welts, pain, blisters, and burning. You can experience these symptoms for up to 8 hours after being in the water. If you are at a lifeguarded beach, seek assistance from the lifeguard. Carefully take out tentacles with a gloved hand, towel, etc. Don’t use your fingers. Applying regular vinegar to the area can be helpful. Don’t rub. If you want, apply heat or cold, which ever feels best for you. If it seems to be getting worse, contact a doctor.
Severe allergic reaction, including anaphylactic shock, can occur. So call 911 if any shortness of breath, weakness, heart palpitations, muscle cramps or severe symptoms occur!
Another nuisance in the Hawaiian waters are the Portuguese Man of War. While they are not very common on most of Oahu’s beaches, they are blown ashore in large numbers when they do visit. Because they are driven by wind they are obviously found on the Windward side of the island,
Most people call the Portuguese Man of War jellyfish, but they are not. They are related to jellyfish, but unlike jellyfish, they cannot swim, they are propelled by the wind. They look like a small, bluish bubble with a long thin tail. In Hawaii, the average size of their bubble is about two inches, with tentacles that can be thirty feet long. The tentacles deliver painful a sting when contacted. Similar to box jellyfish, if you see one on the beach or see someone that has been stung, steer clear of the water. Heed posted warnings and always ask the lifeguards if you have any questions.
Stings are not often fatal, but can hurt a great deal and may lead to an allergic reaction. Symptoms can include: mild burning, redness to severe blisters and welts. If you contact a Man of War, try to immediately take out the tentacles with anything but your bare hands and teeth. Rinse with fresh or salt water but do not use vinegar. Some people will say to do this, but it often makes stings worse. If symptoms are more than mildly uncomfortable, contact a physician.
If you experience any of these symptoms call 911: shortness of breath, heart palpitations, muscle cramps, weakness, or the slightest breathing difficulty.