Rare-colored lobsters keep turning up. Is something fishy going on?

A yellow lobster, donated by a Salem seafood company, will be put on exhibit at the New England Aquarium after it passes quarantine.Emily Bauernfeind/New England Aquarium via Associated Press

On Wednesday, the New England Aquarium in Boston announced it had received a donation of a rare yellow lobster, a “one in 30 million” catch from the coast of Marblehead.

That same day, the Bangor Daily News reported a Maine man had caught a “one in 100 million” white lobster last week.

Those were just the latest examples of what seem to be increasing reports of good-fortuned lobstermen hauling in crustaceans with exceedingly rare hues.

So is it just a healthy dose of lobster lottery luck? Or is something fishy going on with those astronomical odds?

Several lobster experts said they believed the figures to be rough, back-of-the envelope estimates (the aquarium called them “best guesstimates”). But, they said, the odds seem to be in the right ballpark.

“It’s an educated guess,” said University of Maine researcher Robert C. Bayer, who oversees the college’s Lobster Institute.

“In terms of the sniff test, those numbers are pretty accurate and consistent with our anecdotal evidence,” said Tony LaCasse, spokesman for the Aquarium.

One statistic helps put the odds in perspective — the staggering number of lobsters caught in the United States and Canada every year.

Well over 300 million pounds are captured and brought to market by commercial lobster harvesters in the two countries, combined, each year. With the average lobster weighing just a bit over 1 pound, that means about 250 million lobsters are caught annually.

Based on the one-in-30-million figure, you could expect about eight yellow lobsters to surface each year — which makes it all sound a bit less rare, after all.

LaCasse said the yellow lobster announced Wednesday is the first such crustacean that has been caught this year, at least that the Aquarium knows of.

“We should be seeing eight yellows a year, but I can guarantee you we’re not seeing that many,” he said.

He said aquarium staff typically hear about the rare colored lobsters that are found, including ones discovered in Maine and Canada, though it’s possible there are some they don’t know about or that weren’t publicly reported.

“At first glance, given the prevalence of those stories [about rare-colored lobsters], it’s pretty reasonable for your skeptical antenna to go up,” LaCasse said. But, “when you realize that there are hundreds of millions of lobsters that are landed annually — I wouldn’t say it’s hard science but it’s a reasonable estimate for most of those colors.”

Lobsters are normally a greenish, brownish color when alive and only turn that familiar red after being cooked. As for the rare colors:

“It’s a genetic variant,” Bayer said. “The best analogy is eye color in people.”

Other uncommon colors include:

■  Blue: which is said to be a one in 2 million find;

■  Orange: one in 10 million;

■  Red: one in 10 million;

■  Calico: one in 30 million;

■  Split-colored: one in 50 million.

Diane F. Cowan, executive director and senior scientist at The Lobster Conservancy in Maine, said those would have to be rough estimates at best because “we don’t even know how many lobsters are out there.” Experts say the total population of lobsters has never been documented.

But if you think you’ve been hearing about rare finds more often, that might be the case. The number of lobsters caught in the United States and Canada has soared dramatically in the past two decades, which increases the odds of catching lobsters with strange pigments.

Another factor that might be boosting the number of colorful lobster catches: the rise in the prevalence of cameras and social media to document them.

“It’s a cool biological phenomenon,” said Tracy Pugh, senior marine fisheries biologist for the state of Massachusetts. “People get a kick out of them.”