Jellyfish are carnivores and excellent predators. They sting with tentacles to subdue small aquatic fish, and eat the eggs and invertebrates that stick to their tentacles.
Jellyfish are not fish at all, but made of gelatinous material called mesoglea. Ocean currents often pull jellyfish together in large numbers, creating a bloom. Blooms threatens beach-goers, fisheries and tourism. The tentacles have skin with special cells, each with a distinct purpose: to sting, to grip or to stick. Transparency hides jellyfish from predators, but they are slow movers, drifting through the water propelled by their tentacles. Jellyfish are prey for humans, birds, sharks and squid.