Nearly six dozen Box Jellyfish invaded the waters off Waikiki beach, stinging 63 people Wednesday, the city said.
Lifeguards put up warning signs and provided treatment to beachgoers. However, no emergency medical services were needed.
The influx of jellyfish happens every month. Lifeguards say they usually show up along south-facing beaches around 7 to 11 days after a full moon.
Wednesday marked the second day of mass jellyfish sightings. The invasion usually lasts just a few days.
The transparent jellyfish are one to three inches tall, but their tentacles can grow up to two feet long.
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