Sea urchins beware! You are under attack from two sides!
Wrasse and starfish are both partial to sea urchin, but struggle to catch it on their own. So they give each other a helping hand to tackle their common prey.Ornate wrasse like to eat the tube feet of sea urchins, but as the sea urchins keep their feet buried in teh sea bed the wrasse can’t get to them easily. Starfish also likes sea urchin but isn’t always fast enough to catch them.
When a sea urchin is attacked by a starfish, it uproots itself and moves away. That exposes its tube foot, so a lurking wrasse can sweep in for a meal. The wrasse’s feast disables the sea urchin allowing the starfish to catch it and finish the job.
Sea urchins have adhesive tube feet.
The two predators don’t seem to be truly cooperating as neither makes a sacrifice for the other. But their actions nevertheless benefit each other.