"Never Touch Them": The Summer Sea Menace You Must Avoid at All Costs

Sharp Rise in Nomura Gloved Jellyfish Sightings
Signs of Spread Across National Waters
Stings Can Cause Shock or Even Death

Gyeongpo Beach, Gangneung City, Gangwon Province. Unrelated to the main content. Photo by Yonhap News.

As the peak summer vacation season begins, beaches across the country are crowded with people, but beneath the surface, another danger is emerging. Due to the effects of climate change, the appearance of highly venomous large jellyfish is rapidly increasing. In particular, since even simple contact can cause serious health problems, vacationers are urged to exercise special caution.

Appearance rate in Jeju 'doubled'... Spreading to the southern coast

According to jellyfish monitoring results from the National Institute of Fisheries Science on July 8, the appearance rate of Nomura's Comb Jellyfish in the waters around Jeju in the first week of July rose from 36% in 2016 to 80% in 2026, more than doubling over the past 10 years. This is a clear increase compared to the same period last year (55.6%).

This jellyfish is now confirmed to be spreading at low density beyond Jeju to the southern coast, including Jeollanam-do, Gyeongsangnam-do, and Busan. Since it originates along the Chinese coast and moves with ocean currents, the range of its appearance is expanding, especially as summer sea temperatures rise.

2-meter diameter 'giant'... Dangerous even by contact

Nomura's Comb Jellyfish is a giant species with a maximum diameter of 2 meters and a weight of up to 200 kilograms, with highly toxic tentacles. While drifting in the water, it injects its venom through microscopic stingers the moment it comes into contact with a person.

Nomura Jellyfish. Ministry of Oceans and Fisheries

If stung, symptoms may include pain, itching, and skin rashes, as well as fever, vomiting, and muscle pain. In severe cases, it can lead to breathing difficulties or nerve paralysis, and in some situations, even anaphylactic shock that can be life-threatening.

In fact, jellyfish-related incidents continue to occur. Last year, there were more than 2,000 sting incidents reported nationwide, with some cases resulting in casualties. In response, the Ministry of Oceans and Fisheries has raised the jellyfish mass occurrence crisis alert to the "caution" level.

"No freshwater or vinegar"... The correct way to provide first aid

Experts emphasize that along with prevention, an accurate response is essential to minimize jellyfish injuries. If you spot a jellyfish, immediately exit the water and alert a lifeguard. On the beach, avoid walking barefoot. Even dead jellyfish can still be toxic, so do not touch them with bare hands.

If you are stung by a jellyfish, proper first aid is crucial. The most common mistake is rinsing the affected area with tap water or bottled water. Contact with freshwater or alcohol can trigger the jellyfish's nematocysts (stinging cells) by osmosis, causing more venom to be released.

Spraying alcohol or vinegar is also not recommended. Jellyfish stings are a toxic reaction, not a bacterial wound, so vinegar or alcohol should not be used.

The safest way to treat a jellyfish sting is to thoroughly rinse the affected area several times with seawater or saline solution. If tentacles remain after washing the wound, carefully remove them with tweezers or a plastic card, such as a credit card. Avoid rubbing or touching the wound, and do not apply pressure or bandages.

If severe pain, vomiting, breathing difficulties, or other systemic symptoms occur, seek immediate help and visit a medical facility. Children and the elderly are particularly vulnerable to even small amounts of venom and require extra caution.

This content was produced with the assistance of AI translation services.