blue lobsterNot once in a blue moon. Maybe one among 2 million, or 3 million, or possibly 5 million. That’s scientists’ rough estimate of the occurrence of a blue Atlantic lobster.

The color is a breathtaking, intense Prussian blue—and a genetic defect inasmuch as affected baby lobsters stand out like a blue-plate special on the ocean-floor cafeteria. But if one does survive to adulthood—the real rarity—and is hauled up in a fisherman’s lobster trap, it’s almost guaranteed NOT to land in a pot of boiling water. Instead, it will be donated to an aquarium or science center.

In 2009, Shedd received a blue lobster from a Maine shellfish company. Atlantic lobsters, also known as Maine lobsters and Homarus americanus, are native to the colder waters of North America’s Atlantic coast, from Canada’s Maritime Provinces to North Carolina.

The brilliant blue color is the result of a genetic mutation that causes the lobster to produce an overabundance of a large, complex protein called crustacyanin ("cyan" derives from the Greek word for dark blue) that binds the protein for the normal brownish coloration, canceling it out. Even the lobster’s antennae are blue.

Shedd’s blue lobster is about 14 inches long, including the big claws, and weighs about a pound and a half. Because lobsters grow by molting—shedding their hard shell or carapace—at increasingly longer intervals, it’s difficult to estimate age. But these crustaceans are famously long-lived. He (or she—it’s also difficult to tell the difference) molted on July 31 and was photographed while the new shell was still soft, so his color is especially intense. By the next molt, in a year or two, the blue will be slightly dulled by normal algae growth.

Lobsters are scavengers, and this one is no exception, shoveling fish, krill, bits of clam and a special gel diet into his mouth with his smaller front appendages. The two large claws are used for hunting and defense.

The blue lobster is in a reserve enclosure while a large saltwater habitat is closed for renovation. But he’s on the route of our behind-the-scenes tours, so check him out on your next visit.

Posted by Karen Furnweger, web editor