Some sea anemones reproduce sexually while others reproduce asexually.
Individuals of some species of sea anemones produce both eggs and sperm while others are distinctly male or female. They each release their eggs or sperm into the sea. Many species spawn in response to an environmental cue such as a full moon or a low tide so that the eggs and sperm are released simultaneously. The eggs or sperm are ejected through the mouth and when the egg is fertilized, a planula (free swimming larvae) develops, settles to the bottom and grows into a single anemone.
Asexual reproduction is when one indiviual spilts to produce two genetically identical but smaller individuals or clones.
- some sea anemones split longitudinally - they tear themselves apart lengthwise.
- others use pedal laceration where small pieces break off the basal disk and grow into small anemones.
- or budding where part of an anemone protrudes and breaks off forming another anemone.
In general, shallow water sea anemones are smaller and reproduce asexually whereas those in deep water are larger and reproduce sexually. Sea anemones are thought to be very long lived.