The Robust Ghost Pipefish

Coral reefs are renowned for their vibrant colors and charismatic creatures. Sleek reef sharks, bright butterflyfish, and flitting damsels all draw the eye, as you float through their underwater world. However, sometimes the most fascinating animals are the ones that you are least likely to spot.

The robust ghost pipefish (Solenostomus cyanopterus) is extremely well disguised that you will need keen eyes and a bit of luck to distinguish one from the bits of seaweed it likes to hide near. Unlike its cousin, the ornate ghost pipefish (also a remarkable camouflage artist), the robust ghost pipefish has a more subdued color palette. Varieties exist in the whole range of greens and browns, necessary to blend in with their local macro algae. As though its remarkable visual camouflage wasn’t enough, the robust ghost pipefish usually floats near the substrate with its head pointed down, so that even its movements mimic a scrap of seaweed drifting lazily in the current, as shown in the video above.

Rather than scales, cyanopterus is covered in bony plates. This armor and its remarkable camouflage protect the robust ghost pipefish from potential predators. However, cyanopterus is not always the prey. Its ability to blend into its surroundings also hides it from the unassuming little crustaceans that it sucks up through its elongated mouth. Imagine the surprise of a tiny crab, taking shelter in a patch of seaweed only to be vacuumed up and learn that was never seaweed at all.

Like other pipefish, robust ghost pipefish mate for life. Because of this monogamous nature, you will often see cyanopterus floating together in pairs. The female is the larger of the two and has pronounced pelvic fins on her underside, which are fused to form a pouch for incubating eggs. Ghost pipefish are considered “false pipefish” due to the fact that the female of the species carries the fertilized eggs. Among true pipefish, it is the males who incubate the eggs.

Currently, robust ghost pipefish are not classified as threatened, although Australia has given the species a protected status. So if you are lucky enough to dive a reef from the Red Sea to Fiji, take a second look at the little bits of seaweed floating near the bottom. That inconspicuous brown leaf just may be one of the most beautiful and ingeniously disguised animals around.