POSTED: 12:49 p.m. HST, Jul 21, 2014
LAST UPDATED: 3:25 p.m. HST, Jul 21, 2014
More than 800 jellyfish were counted at Waikiki Beach on Monday morning by lifeguards and University of Hawaii researchers, who are studying the stinging creatures.
Lifeguards found 10 jellyfish at Ala Moana Beach and 40 more at Makaha Beach.
Box jellyfish come ashore monthly about 10 days after the full moon on south and west facing beaches on Oahu.
Lifeguards posted signs warning of the jellyfish influx.