ROCKPORT — A local lobsterman found a rarity in one his traps Monday afternoon.
The lobsterman was pulling up his traps in Rockport Harbor when he found a blue lobster in one of his traps.
Blue lobsters occur about one in every 5 million to million lobsters, according to marine biologist Steve Engstrome, the senior aquarist at Rye, N.H.'s Seacoast Science Center at Ordiorne State Park.
The breakdown of rarity in color runs like this, Engstrome said.
Albino lobsters, which present with no color at all, are estimated to occur once in 100 million lobsters; several were found off Cape Ann this summer, including one freed by a reality TV star. One was found off Gloucester in 2010, but was returned to the sea.
Blue lobsters come in at one in every 5 million to 10 million.
Yellow and orange are one in about 30 million.
Calicos, he said, often called leopard lobsters, with a mottled combination of colors, are estimated to be more rare than the yellow and orange variety, but not as rare as an albino.
However, every color but white will turn the traditional red when boiled, according to William Alder, executive director of the Massachusetts Lobstermen's Association.
The lobsterman brought his cerulean catch to the Roy Moore Lobster Co. on Bearskin Neck in Rockport, where it has spent the week in a tank with its normal-looking brethren.
The Roy Moore Lobster Co. is donating the blue lobster to Maritime Gloucester on Harbor Loop in Gloucester.