Many animals in the sea have evolved colors and forms that allow them to blend in with their surroundings. Some animals use their camouflage to hide from predators — and some predators use camouflage to fool their prey.

It can be difficult to photograph such animals, partly because it’s often hard to find them in the first place. If you look carefully at the photo at right, you will be able to make out the shape of a small purplish slipper lobster (Parribacus antarcticus), right in the center of the photo.

The picture was taken inside an underwater cave in Hawaii, and the lobster was on the ceiling. As I shined my light back and forth, the beam passed over the little lobster several times, but I didn’t spot it. Not until it suddenly scurried across the patch of red encrusting sponge was its presence betrayed.

Many animals that dwell primarily on sandy bottoms do an excellent job of blending in with their surroundings. Usually they are pale, with mottling or light patterns that help them mimic the substrate on which they rest. A good example is the flounder (Bothus mancus) in the next photo. I was preparing to photograph something else, and I didn’t notice the flounder until I very nearly knelt on the poor thing.

Sometimes an animal’s eyes are the one feature that will interrupt the camouflage effect and give it away, however this next image illustrates how even a critter’s eyes can be somewhat camouflaged. This is a crocodile fish (Papilloculiceps longiceps), a bottom-dwelling ambush predator from the Red Sea. Take a good look at its eyes and notice the lappets — the small irregular flaps that partially obscure the eyeballs — a part of its disguise.

Speaking of ambush predators, members of the Scorpionfish family (Scorpaenidae) are camouflage champs among fishes. Below is a Bearded Scorpionfish (Scorpaenopsis barbatus) perched on a reef. Decorated with all kinds of little frills, this fellow can be almost indistinguishable from surrounding plants and soft corals.

Next is another member of the same family, a Devil Scorpionfish (Scorpaenopsis diabolus) from Hawaii. This species hangs out around the rocks and dead coral rubble near the edges of reefs, trying its best to look like just another lump as it waits for unsuspecting prey to pass by. Were it not for its fins, it might go unnoticed by the photographer as well as its prey.

Finally, my favorite scorpionfish species, the Leaf Scorpionfish (Taenianotus triacanthus), which comes in quite an array of colors: nearly black, dark brown, purple, pale pink, white, and scrummy yellow like this one. These laterally compressed fishies perch on the bottom, on ledges, or on coral heads to wait for prey. They sway gently back and forth, just as a leaf might. They often are adorned with algae and scaly crud, which enhances their camouflage. This one, photographed in Hawaii, looks like it is about to molt.

In case you are having trouble figuring out which end is which in the photo above, the head is on the right. (Look for the eye and the pectoral fin). Camouflaged fishes and other creatures may not always be the prettiest animals in the sea, but they are among the most interesting of photo subjects. The only problem is locating them in the photo once you get home!