SCOTT SIMON, HOST:
Memorial Day often heralds the reappearance of a lot of summer treats, including the famed lobster roll, the quintessential summer sandwich - lobster meat tossed with mayonnaise, served on a grilled bun. But in Maine there's a mystery brewing around the source of that meat. Some lobsters have been acting strangely this spring. Tom Porter of Maine Public Broadcasting has more on the mystery.
TOM PORTER, BYLINE: April and May are fairly quiet times for Maine lobstermen with the height of the summer season still a couple of months away. But strange things are happening on the ocean floor. Steve Train has been hauling traps for 35 years in Casco Bay, near Portland.
STEVE TRAIN: This time of year when we're lugging our gear in from offshore we see a handful of lobsters and they're usually hard shell lobsters. And for some reason this year as we're bringing the gear home we're seeing shedders in the gear and deep water.
PORTER: The shedders he refers to are soft shelled lobsters which have shed their old casing to grow into a new one. When their bodies have expanded that soft shell hardens. Many lobstermen here began catching shedders in April, four to six weeks ahead of normal. Steve Train says they're outnumbering hard-shelled lobsters about two to one in his traps - and he's puzzled.
TRAIN: That is definitely not normal, and we didn't expect them. I don't know if they'll be here next haul. We might go out next week and they'll be gone.
BOB BAYER: Basically, lobsters grow by shedding their shells. It's called molting and they shed about once a year when they get to be close to market size.
PORTER: Bob Bayer has been studying the biology of lobsters for more than 30 years. He's executive director of the University of Maine's Lobster Institute. Each molt, he says, increases the lobster's size by about 20 percent, but it doesn't normally occur in the spring.
BAYER: As far as I know, it's never happened this early.
PORTER: The signs of early shedding are mostly being seen in the waters of southwest Maine and as for the reasons behind this...
BAYER: We don't know. It's probably a combination of two things that have caused this water temperature - is likely part of it because we did have a warm winter.
PORTER: Another factor, he says, is the availability of food which is often enhanced by the warmer oceans. Peter McAleny owns New Meadows Lobster, which has been dealing crustaceans on Portland's waterfront for 60 years. He's also president of the Maine Lobster Dealers Association.
PETER MCALENY: I've been in the business for 33 years and I've never seen shedders this early, so it's a new test for me.
PORTER: He says shedders are worth about $2 a pound less than hard-shell lobsters because they have less meat on them and are harder to ship. Nevertheless, McAleny sees an opportunity. Many people find the meat on soft-shelled lobsters to be sweeter and much easier to pick. This makes them ideal for making lobster rolls, a favorite with the hordes of tourists who flock to Maine every year, from Memorial Day weekend onwards. For NPR News, I'm Tom Porter in Portland, Maine.
(SOUNDBITE OF MUSIC)
NPR transcripts are created on a rush deadline by a contractor for NPR, and accuracy and availability may vary. This text may not be in its final form and may be updated or revised in the future. Please be aware that the authoritative record of NPR's programming is the audio.