Jellyfish expert Lisa-Ann Gershwin tells CNN's Patricia Wu why the world's jellyfish population is getting out of hand.
Despite being smaller than a pinky nail, the irukandji jellyfish is one of the world's most toxic animals.
courtesy Mike Leahy
A diver attaches a sensor to a large Nomura's jellyfish off the coast of Komatsu in northern Japan. Large schools of these giant jellyfish, which have bodies ranging one to 1.5 meters in diameter, drift into Japanese waters in autumn and damage coastal fisheries.
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A sign warns against swimming in the sea due to the presence of deadly box jellyfish in Darwin, Australia. A 'Vinegar Station' offers a temporary remedy for those who have been stung.
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