Range: Worldwide Habitat: Varies by species Size: Less than 1 inch (2.54cm) to more than 5 feet (1.5m) in diameter Diet: Fish and plankton Threats: Fish, sea slugs, sea stars, sea turtles, and more Life span: Unknown in the wild; Up to eighty years in captivity

Transcript:

Today on Animal Fact Files we’re discussing sea anemones. Not to be confused with the flowers they’re named after, which are called anemones, these soft-bodied marine animals can be found throughout all the world’s oceans from tide pools to the abyss. They can also tolerate brackish water in some cases.

Sea anemones are sometimes likened to underwater flowers as they come with what looks like a thick stalk and petal-like appendages, but sea anemones are animals. The sea anemone’s body plan consists of a soft, tube-like body which may be thick and short, long and slender, or everything in between; an oral disc through which both food and waste passes - this is surrounded by stinging tentacles which capture food, there may be dozens to hundreds of these tentacles; and finally a base which settles these animals to the sea floor or other objects.

Some sea anemones, however, don’t attach to the bottom and instead bury themselves in substrate up to their tentacles or float through the water column with their tentacles hanging downward! Like sea urchins, some anemones may cover their bodies in debris like shells and rocks. In size, sea anemones range from less than an inch (2.54cm) to more than five feet (1.5m) in diameter depending on the species - of which there are somewhere around 1,000 alive today. Sea anemones can even puff up to appear larger!

Sea anemones are invertebrates meaning they don’t have a backbone. They are typically separated by sexes and thus release sperm or eggs to be fertilized by other members of their species. Some female sea anemones keep their eggs inside their bodies to be fertilized inside. Free-swimming larvae hatch from the eggs and eventually settle to the sea floor.

Other anemones may reproduce asexually with some literally splitting in half or even smaller pieces to produce new individuals. It’s not entirely understood how long sea anemones are able to live, however, some species have been known to reach 80 years of age in captivity!

Sea anemones have stinging tentacles to capture other animals such as fish and planktonic animals. These tentacles then guide the food to the single opening in the oral disc, which is located in the middle of all the tentacles. Often the sting of an anemone will keep predators away, however, they may be eaten by some fish, like flatfish and eels, as well as sea slugs, sea stars, sea turtles, and more.

Some animals, like clownfish, are well known for living among stinging sea anemones as the invertebrates provide the fish protection while the fish can provide the anemones food. These animals are typically sessile, meaning they don’t move around much, but some anemone species do move slowly by creeping along the ocean floor sometimes in a somersault fashion! Others may live on other animals and move with them - for example some may live on the shells of hermit crabs!

For more facts on sea anemones, check out the links in the description. Thank you to Edy for today’s request! Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files!