For Luigi the lobster, it was simply time to grow up. Literally. The American boneless lobster (American Homarus) recently molted (when a crustacean sheds its outer shell) in front of visitors to the New York Aquarium in Brooklyn. Luigi is an unusual shade of orange that is only seen in one in 30 million American lobsters.

“On the morning in question, the keeper staff discovered a molt in Luigi’s habitat,” says William Hana, director of animal programs at the New York Aquarium. popular science.

“In our experience, molting usually occurs during the afternoon hours and can continue throughout the night. After molting, Luigi showed the bright coloration characteristic of a newly formed shell.”

Luigi the dumb lobster

During molting, crustaceans absorb excess water. The water then pushes against the shell and breaks it. The lobster then pulls out the rest of its body like pulling a foot out of a shoe, while shedding its old outer shell. A shiny new soft shell then emerges as the animal’s exoskeleton.

That new shell is soft and paper-thin, so the crustaceans are more vulnerable after molting. Since Luigi was housed alone at the time, he didn’t have to worry about predators or aggressive behavior from other animals.

Young lobsters tend to molt several times a year because they grow faster. Once they reach adulthood, lobsters tend to molt annually. Molting rates can vary between lobsters in human care like Luigi and those found in the wild. Since aquarium lobsters live in a protected habitat with constant feeding, they can usually devote more energy to growing rather than searching for food and avoiding predators. However, a food source is constant no matter where the lobster lives.

“Lobsters often consume their exoskeleton after molting,” says Hana. “This behavior allows them to recover calcium and other essential minerals needed to harden their new, soft shell. For this reason, our staff typically leave the shell in the habitat for several days after a molt to give the animal a chance to feed on it.”

American lobsters are usually a dark blue-green or greenish-brown color, but Luigi’s rare orange hue makes it look a little more like a lobster you might find on a plate.

It gets its color from a genetic mutation caused by a lack of proteins that help bind pigments in its shell. The chances of finding an orange lobster like Luigi in the wild are about one in 30 million. It can also be seen near a rare blue lobster (one in 200 million). Happy growing, crustaceans!

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