Sea anemones can move in two distinct ways, either by using their single powerful foot to glide slowly across surfaces or by swimming with the current by flexing their muscular stalk. Anemones appear immobile and most do not move for the majority of their lifespans, but almost all anemones are capable of one form of locomotion or another and will move to seek out prey.
While anemones can move, they generally remain stationary in and around coral reefs, to which they are related. They use their stinging venomous tentacles to immobilize prey and then slowly digest that prey to give themselves the nutrients they need to reproduce.
Anemone tentacles contain biological structures called spears which can be propelled out of the tentacle and into prey at short range. These spears deliver painful and potentially deadly jolts of a venom to which the anemone itself is completely immune, meaning that it is free to eat what it kills with impunity.
Anemones are known for their ability to retract their tentacles when they are threatened, allowing them to hide within the protection of their durable bodies. They may also use the current to their advantage in a defensive sense, detaching so that they are carried away from predators.