Many animals have interesting coloration, behaviors and morphology (body shapes) that serve as camouflage. This keeps them hidden from predators and allows them to go about their daily business unscathed. Many fish, crabs and other animals in the Long Island Sound exhibit spectacular forms of camouflage.
Spider crabs, Libinia sp.
The body (carapace) of the spider crab can grow to be 4 inches long and sports numerous spikes and knobs. These crabs have an olive to white shell, yet they almost always appear brown and fuzzy! What could cause this? There are numerous algae that grow on them and allow them to blend in with the surrounding habitat. Oddly enough, the crabs will utilize the algae as a food source and can be seen using their claws to graze a snack off their backs.
Spider crabs are also known as “decorator” crabs. They obtained this name from their habit of picking up pieces of substrate, stones, shells, seaweed, and debris, coating them with a glue-like substance secreted from the mouth, and sticking them onto small hooks on their backs. This renders the crabs nearly invisible and keeps them safe from predators.
Windowpane flounder, Scophthalmus aquosus and winter flounder, Pleuronectes americanus
Flounder species are bizarre “flatfish,” meaning they have their fins, eyes, and mouth on one side of their head. They primarily spend their time one the sea floor, sometimes burying in the sand with only their eyes exposed. The flounder’s pattern looks exactly like the sandy, rocky sea floor. Many times our visitors stare right at a flounder in a Seaside Center aquarium and cannot see it, even after we point one out.
Sea robin, Prionotus evolans
Sea robins have large, fan-like fins and armor covered skin instead of scales. They sometimes take refuge on the sea floor, and the large fins help break up their outline when viewed from above, giving them an unfish-like appearance. The adults are grey-olive in color with flashes of orange on the fins and body, yet the young are mottled black in color. This coloration lets them blend in perfectly with rocks, shells, and debris on the sea floor. This, along with the fins, disturbs their outline and makes them all but disappear to would-be predators.
Oyster toadfish, Opsanus tau
This is a medium-size, stocky fish, which has an ambush style of hunting. They tend to live in rock caves, crevices, under seaweed mats, and inside miscellaneous debris. They are rather drab in color and are adorned with numerous flaps of skin around their head and face. They will sit motionless in a hiding spot and wait for an unsuspecting fish, crab, or shrimp to come near, then dart out and gulp the prey down.