Giant Jellyfish

Giant jellyfish are taking over parts of the world's oceans as overfishing and other human activities open windows of opportunity for them to prosper, say researchers.

Jellyfish are normally kept in check by fish, which eat small jellyfish and compete for jellyfish food such as zooplankton, researchers said. But, with overfishing, jellyfish numbers are increasing.

These huge creatures can burst through fishing nets, as well as destroy local fisheries with their taste for fish eggs and larvae.