PORTSMOUTH, N.H. – First it was flags. Then it was Christmas lights. Now, even lobsters are displaying patriotic colors.

In May, a rare blue lobster turned up about 80 miles off the coast of Kittery, Maine. In September, a Portsmouth fisherman caught an albino lobster in the Piscataqua River. The patriotic trilogy was completed earlier this month when a live red lobster turned up in a trap about five miles off the Isles of Shoals.

The odds of finding a blue lobster are about 1 in 2 million. For a live red lobster, it is about 1 in 10 million and for an albino lobster it is about 1 in 30 million.

Simple statistics explain the findings, said Diane Cowan, senior scientist at the Lobster Conservancy in Friendship, Maine.

Given that more than 50 million lobsters were caught off the New England coast last year, “you expect to see at least one” albino lobster, and even more of the less rare blue and red specimens

While the color of a lobster can be determined by genetics, it can also be determined by a lobster’s diet. Lobsters need to eat enough of a type of food that contains the pigment astaxanthin to maintain their natural color.

Cowan said the lobsters eat other fish that have digested plankton containing astaxanthin. The pigment bonds to the lobsters’ shells.

When lobsters are cooked, all the pigment is destroyed except for the red-colored pigment. If lobsters do not get enough astaxanthin, they will not be the usual greenish-brown.

“You feed lobsters nothing but squid, that’s going to determine their colors,” she said.

Robert Bayer, executive director of the Lobster Institute at University of Maine’s Orono campus, said he thinks that more people are bringing these differently colored lobsters to the public because of the attention they receive in the media.

Lobsters that are a different color because of genetics can pass on the trait through breeding, Bayer said.

“It’s a genetic trait comparable to eye color in people,” he said.

The Science and Nature Center at the Seabrook nuclear power plant has been home to another blue lobster that was found in Maine last year.

The crustacean, dubbed “Chilly Willie” originally was donated to the Portland Children’s Museum. But officials transferred it to the Seabrook center because it had proved too disruptive to other sea creatures.

“He’s doing great,” said Alan Griffith, spokesman for Seabrook Station. “He’s adjusted quite nicely to his new environment.”

The center has been closed to the public since the Sept. 11 terrorist attacks, but Griffith said officials will reopen it as soon as possible.