City officials were to check Hanauma Bay Nature Preserve early Saturday and consider whether to reopen it after the beach was closed Friday because of an influx of jellyfish.

Hanauma’s beach was closed at 10:21 a.m. Friday, but the upper area stayed open for people to enjoy the scenic view.  

Honolulu Ocean Safety has issued a jellyfish warning for Hanauma Bay and a jellyfish advisory in the areas of Kai-lua Beach and Lani-kai. Box jellyfish come ashore monthly about 10 days after the full moon on south- and west-facing beaches on Oahu. The last full moon was Feb. 3.

A spokeswoman for the Ocean Safety Division said there were 80 stings at Hanauma Bay Friday morning and lifeguards counted 100 jellyfish on the beach.

Paramedics responded twice to Hanauma Bay for three patients who had allergic reactions to the stings. None of the three needed to be taken to the hospital.

Four people reported jellyfish stings at Kailua Beach Park and lifeguards counted 100 jellyfish Friday morning.

Lifeguards will reassess the situation Saturday morning to see if the bay should reopen.

Box jellyfish come ashore monthly about 10 days after the full moon on south and west facing beaches on Oahu. The last full moon was Feb. 3. The next full moon is March 5.

The influx normally affects Ala Moana and Waikiki beaches. But jellyfish will also come ashore at other beaches.

Box jellyfish typically measure 1 to 2 inches long, with tentacles that stretch about a foot long. Even those that are lying on the sand can be toxic and should not be touched. Beachgoers who are stung can use an ice pack or immerse the wound in warm water to relieve the pain,