In Rockingham they also have dolphin trips and one of the tour operators gets you in snorkelling with dolphins. Billy Connoly did it with the same operator on his Australian tour. We may do that in January but gave it a miss this time.
Getting on the ferry was easy. The Island isn't far away. You can swim or paddle a kayak across if you want. Some people even walked across (at low tide the sand bar is no more than waist deep).
On the Island there's an opportunity to see the penguins during feeding time.

I'm being a statue.

A colony of Pelicans have settled on the Island but access is restricted to avoid scaring them off, hence the distant photo. These are big birds but you already knew that from "Finding Nemo".