Nomura's Jellyfish (Nemopilema nomurai)

Nemopilema nomurai, one of the largest Cnidarians in the world.


Nomura's jellyfish is a very large jellyfish that can grow up to 2 meters (6.6 ft) in diameter and weigh around 400 lbs. That means that the diameter is longer than an average adult man! They are orange in color. Their name is deprived from Kan'ichi Nomura who captured a specimen and studied it in 1921 because it was largely unknown. These jellyfish are mostly found in the waters between China and Korea, and more recently Japan, due to global warming. They are mostly condensed in the Yellow Sea and East China Sea. Their venom is not very deadly humans; a sting is very painful, but it is not toxic enough to seriously injure a human. But they are still able to kill one, if people are not careful. When they are being attacked or dying, they release billions of sperm or eggs that would latch on to surrounding rocks or coral. A baby Nomura's jellyfish can grow from a few millimeters to a meter in diameter in only six months. Not much is known about this jellyfish, because only recently has a large number of them appeared closer to coasts and sparked an interest in researchers.

Unwanted Nomura's jellyfish usually end up in fishing nets, ruining the catch or capsizing boats.
Unwanted Nomura's jellyfish usually end up in fishing nets, ruining the catch or capsizing boats.

Affect on people

Nomura's jellyfish are becoming a major problem to fishermen in Japan. They are common in China's and Korea's waters, but recently in Japan their population has increased by thousands. A theory for this explosion is global warming, because warmer waters are ideal breeding conditions for Nomura's jellyfish. Global warming is also the cause for recent jellyfish migration worldwide. In Japan, ten of thousands of Nomura's jellyfish are living in fishing hotspots. They usually get caught up in fisher nets, ruining the catch or destroying the nets because of their immense weight. They sting and kill the catch or crush them to death. In one incident, a boat was capsized by dozens of Nomura's jellyfish. The Japanese government has called for studies on the species mating and migration habits. Some Japanese companies are trying to make cash from the increased number of jellyfish, some examples are selling jellyfish-flavored ice cream, dried or salted snacks, fertilizer for land, or even skin products(collagen extracted from the jellyfish has been shown to be beneficial to skin).

Nomura's Jellyfish
Nomura's Jellyfish


Kingdom: Animalia
Phylum: Cnidaria
Class: Scyphozoa
Order: Rhizostomae
Family: Stomolophidae
Genus: Nemopilema
Species: N. nomurai

Link to video of Nomura's Jellyfish: