Wednesday, October 27, 2010

Video of Cuttlefish Hunting

I mentioned in my earlier post that cuttlefish not only use their camouflage to hide, but also to confuse their prey. I finally found a good video of a cuttlefish trying to do this. This is a great example of how quickly the skin of a cuttlefish can change colors too.



In this case its prey is actually a plastic toy put there by a scuba diver, so it's attempts to confuse it don't seem to get much of a response. The only one confused here is the cuttlefish. The next video shows a cuttlefish hunting real fish.



When the diver gets too close, the cuttlefish suddenly switches from hunting prey to camouflaging from what he sees as a predator.

Monday, January 25, 2010

Cuttlefish

Cuttlefish have some of the most incredible camouflage of anything in the animal kingdom. Their highly complex brain allows them to control the cells in their skin to blend in perfectly with their surroundings, or flash colorful displays much like an LED billboard.

The cells on the skin of a cuttlefish are covered in tiny dots of all colors, much like the tiny dots that make up the screen of your computer. A cuttlefish can make their cells grow or shrink to bring out the perfect blend of colors to match whatever is around it.



Its skin can also change shape from its usual smooth texture to whatever matches its surroundings. When it combines its color and texture adaptation, a cuttlefish can become nearly invisible even in plain sight. Because it can change its camouflage almost instantly, cuttlefish are very good at stalking prey, or avoiding becoming a meal themselves.

Cuttlefish are excellent predators, feeding on small fish and crustaceans. They will sneak up on their prey until they are close enough to strike, then shoot out two of their longest tentacles like harpoons to grab onto their prey with their suction cups. Then they reel their victim back into their mouth. Cuttlefish will also sometimes flash waving patterns of bright colors to confuse their prey while they move in for the kill.

Cuttlefish are not actually fish as their name implies. They are mollusks, close relatives of octopus and squid. Unlike their boneless cousins, cuttlefish have an internal shell which acts a skeleton to help them hold their shape. Cuttlefish shells are often sold at pet stores as calcium supplements for birds.

Cuttlefish use their skin for more than just camouflage. They can also use their amazing control of color to communicate. They often change to bright colors when they are angry to warn other sea creatures or other cuttlefish to stay away. They also use their arms to communicate, holding them in certain positions as if they are using sign language.

I once found a cuttlefish while I was snorkeling in Cozumel. Unlike most marine life, it seemed genuinely curious about me. I swam in close and moved my fingers into the position it had its tentacles in. It waved its arms back and flashed bright colors at me as if it was trying to carry on a conversation. After a few minutes, the cuttlefish darted away and disappeared. I still wonder if I said something mean or just wasn't much fun to talk to.