The Norman Transcript

Nation/World

December 2, 2012

Rings show lobster age

PORTLAND, Maine — For the first time, scientists have figured out how to determine the age of a lobster — by counting its rings, like a tree.

Nobody knows how old lobsters can live to be; some people estimate they live to more than 100.

But knowing — rather than simply guessing — their age and that of other shellfish could help scientists better understand the population and assist regulators of the lucrative industry, said Raouf Kilada, a research associate at the University of New Brunswick who was the lead author of a scientific paper documenting the process.

Before now, scientists deduced a lobster’s age judging by size and other variables. But it’s now known that lobsters and other crustaceans, such as crabs and shrimp, grow one ring per year in hidden-away internal spots, Kilada said.

“Having the age information for any commercial species will definitely improve the stock assessment and ensure sustainability,” he said after presenting his findings Thursday at a scientific conference in Portland.

Scientists already could tell a fish’s age by counting the growth rings found in a bony part of its inner ear, a shark’s age from the rings in its vertebrae and a scallop or clam’s age from the rings of its shell.

But crustaceans posed a problem because of the apparent absence of any permanent growth structures. It was thought that when lobsters and other crustaceans molt, they shed all calcified body parts that might record annual growth bands.

For their research, Kilada and five other Canadian researchers took a closer look at lobsters, snow crabs, northern shrimp and sculptured shrimp.

They found that growth rings, in fact, could be found in the eyestalk — a stalk connected to the body with an eyeball on the end — of lobsters, crabs and shrimp. In lobsters and crabs, the rings were also found in the so-called “gastric mills,” parts of the stomach with three teeth-like structures used to grind up food.

Text Only | Photo Reprints
Nation/World
  • Judge asks pointed questions in gay marriage case

    DENVER — A judge in Colorado who will play a pivotal role deciding whether gays should be allowed to wed in the United States asked pointed questions Thursday about whether Oklahoma can legally ban the unions....

    April 18, 2014

  • Sudan: 12 die after mob attacks UN base

    JUBA, South Sudan — An angry mob of South Sudanese youths attacked a U.N. base on Thursday to harm members of an ethnic minority sheltering inside. Peacekeepers were forced to open fire, amid rampaging violence that killed at least 12 ...

    April 18, 2014

  • Astronomers spot most Earth-like planet yet

    LOS ANGELES — Astronomers have discovered what they say is the most Earth-like planet yet detected — a distant, rocky world that’s similar in size to our own and exists in the Goldilocks zone where it’s not too hot and not too cold for ...

    April 18, 2014

  • Creek, old purse solve mystery

    ELK POINT, S.D. — Cheryl Miller and Pamella Jackson had planned to celebrate the end of the 1971 school year by gathering with classmates at a quarry along a gravel road....

    April 18, 2014

  • Chaotic scene described on sinking ferry

    MOKPO, South Korea — There was chaos and confusion on the bridge of a sinking ferry, with the captain first trying to stabilize the listing vessel before ordering its evacuation, a crewman said Thursday....

    April 18, 2014

  • Tiny power plants hold promise for nuclear energy

    PARIS — Small underground nuclear power plants that could be cheaper to build than their behemoth counterparts may herald the future for an energy industry under intense scrutiny since the Fukushima disaster, the incoming head of the ...

    April 18, 2014

  • Organizers confident of safe race

    BOSTON — The arrest of a man with a rice cooker in his backpack near the Boston Marathon finish line led police to step up patrols Wednesday, while organizers sought to assure the city and runners of a safe race next week....

    April 17, 2014

  • Ukraine bares teeth against eastern uprising

    KRAMATORSK, Ukraine — In the first Ukrainian military action against a pro-Russian uprising in the east, government forces repelled an attack Tuesday by about 30 gunmen at an airport, beginning what the president called an “anti-terrorist ...

    April 16, 2014

  • Supremacist faces murder charges

    OVERLAND PARK, Kan. — The white supremacist charged in shootings that left three people dead at two Jewish community sites in suburban Kansas City made his first court appearance Tuesday....

    April 16, 2014

  • Iran cuts nuclear weapons ability

    VIENNA — The United Nations will release a report this week certifying that Iran’s ability to make a nuclear bomb has been greatly reduced because it has diluted half of its material that can be turned most quickly into weapons-grade ...

    April 16, 2014