by Dr. Lenore Tedesco, Executive Director, and Devin Griffiths, Marketing & Communications Specialist
What has eight arms, can change colors at will, and is an expert escape artist? An octopus, of course!
Octopuses are remarkable, and in coastal New Jersey, the Common Octopus (Octopus vulagris) is a fascinating resident of our local waters. This species of octopus is found throughout the world’s oceans, in tropical and temperate zones. However, people rarely see octopuses in the wild, and most know very little about these incredible creatures. Lucky for you, you can find one right here at The Wetlands Institute, in our Secrets of the Salt Marsh aquarium, waiting to provide a unique up-close opportunity to learn more about these amazing creatures.
Common octopuses vary in length from about 12 inches to three feet. All that growth is fueled by a strict seafood diet. In the wild, they prefer to feast on crabs, clams, and mussels, but will eat virtually anything they can catch. They crush shells with their hard “beaks” and catch prey in powerful webbed arms lined with super-sticky suction-cup-like suckers. Octopuses shed the lining of their suckers periodically to keep them sticky. Once captured, they paralyze their prey with a nerve poison present in their saliva.
In addition to their signature arms, octopuses are equipped with a host of fascinating features. The most obvious is their bulbous head (or mantle), which they can force water through to propel them forward. They also have three hearts, use cooper (not iron) as the oxygen-carrying pigment in their blood, and, while not their primary mode of respiration, they can even absorb oxygen through their skin.
Octopuses are adept at protecting themselves from predators, and when threatened they can release a cloud of ink into the water. This ink dulls a predator’s senses of vision and smell, helping to confuse it while the octopus escapes. If the going gets really tough, an octopus can sacrifice an arm to a predator and grow it back later!
Their preferred method of defense, however, is hiding – and they have some special tricks to do this. Little of an octopus’ body is solid, allowing them to squeeze into exceedingly small spaces. They also collect shells and other objects to build fortresses around their lairs. The pièce de résistance, though, is their ability to disappear. Octopuses are masters of disguise and can change the color and texture of their skin to blend in with their surroundings. They use a network of tiny, color-changing cells called chromatophores that line their entire body just below the surface of the skin. Octopuses can constrict or relax these special cells, causing varying levels of pigment to appear – allowing them to take on colorations from red or red-brown to light pink or near white. Specialized muscles in their skin also allow them to change skin texture. This combination allows octopuses to rapidly shift colors and patterns to match their environment.
Behind all of these defenses is a highly developed neurological system. Octopuses are believed to be the most intelligent of all invertebrates, possessing large brains and a network of neurons distributed throughout their arms. These neurons function as little sub-brains, allowing each arm to taste, touch, smell, and act independently – no input from the main brain required! Octopuses can determine the size and shape of objects, remember patterns, navigate mazes, and solve problems – and they are the only invertebrate known to use tools. With an expected lifespan of only one to two years, these incredible, intelligent creatures live short but mighty lives.
So, are you ready to meet one? Our resident octopus, Gary, is still on the younger side, measuring in at under a foot long, but growing each day. He is a fast learner, enjoys hunting live prey, and can open a variety of containers to eat a mix of local seafood including crabs, mussels, and fish. Gary has favorite toys, and is curious about new people. Come on out and spend some time with him. You’ll be surprised at what you discover, and you might leave having made a new friend.