Shipwrecks could explain the mysterious spike of killer jellyfish invading shorelines, experts say.
The box jellyfish population has soared since the 1980s and humans can suffer a deadly cardiac arrest within minutes if they have been stung.
Experts in Hawaii say the rise in jellyfish can be attributed to shipwrecks, a study reveals.
The YO-257 US Navy vessel was deliberately sunk around two miles off the coast of Waikiki in 1989.
The San Pedro and Sea Tiger are also among wreckages at the bottom of Mamala Bay, the San Francisco Gate revealed.
Researchers say the shipwrecks have become artificial reefs for jellyfish, the Weather Channel reported.
But, experts have said that the declining populations of sea turtles and fish could also explain the rise in jellyfish colonies.
Sometimes, the beasts have washed ashore, posing a risk to humans.
Officials have had to close beaches as a precaution.
Humans can potentially suffer a deadly cardiac arrest if they have been stung by a box jellyfish.
Scientists say the beasts punch holes in red blood cells, causing potassium to leak out.
Renowned biochemist Dr. Angel Yanagihara told ABC News: “The box jellyfish is the most venomous animal in the world.”
Yanagihara revealed the beast has 60 two-meter long tentacles that are covered in stinging cells.
The scientist said the fastest deaths have occurred within two-five minutes.
But, some stings can lead to death four to 18 hours after the event, health experts say.
Yanagihara also said: “The leakage of massive amounts of potassium from red blood cells is one of the worst things that could happen in the body.
“When the plasma potassium gets too high, there’s no more electromotive force and the heart cannot beat.”
Box jellyfish are commonly found in Hawaii, Florida, the Caribbean, Puerto Rico, and Australia.
They are named after their distinctive shape and can be known as sea wasps.
Common symptoms that may emerge as a result of a sting include red lesions, known as wheals, severe chest pains, fever, and nausea.
Those that have been stung shouldn’t try to treat the wound with fresh water or alcohol as it could spread the venom.
Health officials warn that the sting shouldn’t be ignored.
The Sun revealed how Brit holidaymaker James Soale was left fighting for his life after coming into contact with a deadly Irukandji jellyfish during his dream vacation in Australia.
And, in February, a 14-year-old teen boy died after being stung by a box jellyfish in Queensland.
This story originally appeared on The Sun and was reproduced here with permission.