- Odontaster validus
This species of sea star lives throughout Antarctica at depths up to 915 meters! It grows to be about 7cm in diameter and takes ~9 years to reach the population average weight of 30g. It is estimated to live for up to 100 years! This sea star is near the top of the food chain in the Antarctic seafloor ecosystems and is a voracious predator akin to the lions of the Serengeti! It eats many things including, but not limited to detritus, small crustaceans, other sea star species, scallops, bryozoans, sponges, sea urchins, and worms.
2. Acondontaster conspicuous
This species of sea star lives throughout Antarctica at depths up to 760 meters! It grows to be about 14cm in diameter. This species eats many species of sponges. They often aggregate and gang up on a single sponge, eventually killing it. The previous red species of sea star (Odontaster validus) gang up to feed on the Acodontaster species (as shown below in Norbert Wu’s photo), and by doing so keep the population in check. Otherwise, this yellow species would get out of control and decimate the sponge populations.
3. Diplasterias brucei
The yellow sea star Diplasterias bruceii lives throughout Antarctica at depths up to 752m and grows to be about 24 cm in diameter. This is a specialized predator of molluscs including bivalves and gastropods.
Also in the image above:
- The featherduster worm (AKA: a sabellid polychaete worm) belongs to the genus Perkinsiana. It is found throughout Antarctica at depths ranging from 3 to 800m. It grows up to 20 cm long. It possesses a crown of feeding appendages (radioles) and uses these to filter seawater for food. They can be tricky to photograph because if you get too close or spook them, they retract their radioles down inside their protective tube which is made of calcium carbonate.
- The proboscis worm Parborlasia corrugatus lives throughout Antarctica at depths up to 3590m and grows to lengths of one to two meters, a diameter of two centimeters, and weighs up to 100g! Parborlasia corrugatus is a scavenger and a predator with a voracious appetite, and will eat almost anything; its diet includes sponges, jellyfish, diatoms, seastars, anemones, polychaete worms, molluscs, crustaceans, and fish. It can detect food at a distance with an efficient chemotactic sense. It has a large mouth and can consume prey almost as large as itself! Finally, they produce a lot of slime
