Eye candy only.

As I was casting about for a blog idea for today, I remembered the rock pool hopping I did with my daughter yesterday. She is doing a school project on echinoderms (starfish, sea cucumbers, sea urchins), and we went looking for them. I know sea cucumbers are eaten in some Asian countries, and sea urchins (kina) are a traditional Maori food, and I was curious whether starfish were edible. The short answer is that apparently some people eat their gonads, but the rest of them is poisonous. Of course! I should have recognised that by their bright colours—those warning colours that so many animals use to advertise their toxicity.

Their poisons include tetrodotoxin, the same neurotoxin found in the infamous puffer fish, and saponins that can cause red blood cells to burst.

And that, of course, explains how these easily spotted, slow moving denizens of shallow rock pools avoid being eaten by the gulls, herons, and oystercatchers that prowl the shore.

So next time you’re at the beach, take your lunch with you and leave the starfish alone.