By Jung Min-ho

Korea is not known for deadly sea animals, but its southern coasts are increasingly becoming home to two such creatures ― blue-ringed octopuses and black-banded sea kraits.





blue-ringed octopus

Since a blue-ringed octopus was found two months ago in Geoje, a southern coastal city, the city government has set up warning signs in the area.

The octopus is one of the world's most venomous marine animals. It is about the same size as a golf ball but one octopus is known to carry enough venom to kill 26 adults within minutes. Its venom, which contains a neurotoxin among other poisons, can result in paralysis, blindness, respiratory arrest, heart failure and death by suffocation if not properly treated.

Coral reefs in the Pacific and Indian Oceans, from Japan to Australia, are known to be the octopuses' habitats. But since the octopus was found on Jeju Island in 2012 ― the first case in Korea ― it has so far been found in its four southern cities ― Yeongdeok, Ulsan, Uljin and Geoje.

According to a report released in June, a research team at Kangwon National University has also found 12 black-banded sea kraits around the south coast and Jeju Island between April 2015 and October 2016 ― also a first in Korea.

black-banded sea krai

The snake's venom is believed to be 10 times stronger than that of a cobra, making it highly dangerous if provoked, though it rarely attacks humans first.

Some experts, including Park Dae-sik, a university professor who led the research, believes rising sea temperatures near the Korean Peninsula is one of the key, if not only, reasons why many such sea creatures have been found in the country in recent years.

So far, there has been one reported case in which a person was bitten by either of the two. In 2015, a man was hospitalized after a blue-ringed octopus bit his hand, but he survived after prompt treatment.