Postcard from the Reef – Sea Star

Gliding across the sand, a handsome sea star catches my eye. These stars spend the day under the sand, hiding from the many predators that hunt with the light. In the darkness it rises and begins its own hunt. While two arms seem to be in the process of regrowing, the star is otherwise quite healthy. I wander off into the dark, wondering what prey the starfish is seeking, what will be eaten tonight.

A starfish (Luidia aspera) hunting across the sand at night, 40′ depth, Mahukona

Postcard from the Reef – Regeneration

You may know that a starfish can regenerate a lost limb. Seeing it in process? More extreme… A single limb regrowing the rest of the body? It is a bit surprising to see such a bold example of regeneration in process.

The limb may have been parted by injury. Another possibility here is reproduction. Some species reproduce by simply detaching an arm in a process called autotomy. The detached arm becomes a new individual. An impressive capability indeed.

Regenerating Linckia
A green linckia starfish (Linckia guildingi) in the process of regenerating from a single arm

Postcard from the Reef – Cushion Star Underside

You see these starfish often enough, they are fairly common on the reef. Often taking a closer look at the commonplace will show something worth a photo. In this case a closeup of the underside of the starfish, a truly odd creature…

Cusion Star Reverse
The underside of a cushion star (Culcita novaeguineae)

Postcard from the Reef – Cushion Star

I have occasionally seen these starfish tucked into the coral by day. When you see just a small part of the animal it is not immediately recognizable as a starfish, just a lump of something that does not match. They emerge at night to feed on the coral itself. Once in the open the five-fold symmetry begins to suggest that you might be looking at a starfish…

Cushion Star
A cushion star (Culcita novaeguineae) on the sand at 40′ depth, Mahukona