HONOLULU -- Lifeguards on Tuesday morning found about 50 box jellyfish in the pond area of Kuhio Beach in Waikiki and said more is on the way.

That is a small number of jellyfish for a day during the monthly invasion, according to Water Safety Division officials.

Officials said they expect the majority of the jellyfish to wash ashore on Wednesday and Thursday.

Beaches on the south shore such as Ala Moana, Waikiki, Hanauma Bay and Pokai Bay are usually affected. Makaha Beach is also commonly hit during jellyfish inundations.

The jellyfish can cause a painful sting that can be dangerous for those who are allergic to the toxins.

Officials said that pouring vinegar over the affected areas can help ease the sting. Anyone who suffers breathing problems, muscle spasms or constant pain should get immediate medical attention, ocean safety officials said.

Swimmers are advised to check with lifeguards, who are also equipped to treat the stings.