A large influx of box jellyfish along Oahu shorelines is turning a long holiday weekend into a painful one for many and it could get worse Monday on the Presidents Day holiday.

In fact, it’s expected to last through Tuesday, so keep an eye out for warning signs and talk with a lifeguard before taking a dip in the ocean.

“We’ve had these animals coming in every lunar cycle without fail since the late, mid ’90s, before that they were known sporadically, but throughout the whole from Diamond Head, all the way to Ala Moana Beach, we see these each month,” said box jellyfish expert Dr. Angel Yanagihara with University of Hawaii.

According to Ocean Safety lifeguards, there were 1,035 jellyfish sightings and 23 stings reported Monday at Ala Moana Beach and Waikiki, and at Hanauma Bay, there were 10 sightings and 25 stings.

On Sunday, lifeguards said that there were 50 jellyfish stings and counted roughly 460 box jellyfish along the shoreline at Ala Moana and Waikiki.

At Hanauma Bay, lifeguards reported 31 stings and roughly 20 box jellyfish on the shoreline.

Lifeguards posted signs in all impacted areas and gave verbal warnings to beach goers.

None of the stings on Sunday required the attention of Emergency Medical Services.