Welcome to the Marine Mili series, a regular column about all things marine! During this series I aim to inspire people to want to protect our oceans and all the marine life that call our oceans home. Hopefully after reading each column, you would have learnt something new including what we can do to help protect and preserve our oceans. You can follow me and my journey on my Instagram page: _marine_mili.

This week, we'll look at the Eleven-armed Sea Star, which is native to Australia’s southern waters.

There is a large known population in Port Phillip Bay and if you ever go for a dive or snorkel under a pier, you will see many of them around.

Whenever I go for a scuba dive on the Mornington Peninsula, I see scores of them hanging out under piers - sometimes more than twenty of them in the same spot.

This species has the ability to regenerate their arms if they lose one.

Often they'll be spotted missing arms, or have smaller arms that are in the process of re-growing.

An interesting fact. Did you know sea stars have eyes on each arm? This means a sea star with five arms has five eyes and this species, the Eleven-armed Sea Star, has 11 eyes.

They can grow up to 50cm in diameter, typically feed on sea urchins, mussels, smaller sea stars and occasionally other creatures including worms and crabs.

Recently, scientists have discovered them feeding on young Northern Pacific Sea Stars which is new behaviour.

The Northern Pacific Sea Star is a marine pest, also referred to as the Port Phillip pest.

By the Eleven-armed Sea Star becoming a predator to the destructive Northern Pacific Sea Star, it's helping control the population which benefits the environment.

You can learn more about the Northern Pacific Sea Star in a previous column here.