Age and growth laboratory

The Massachusetts Division of Marine Fisheries Age and Growth lab determines the ages of several species of fish. These ages are used to help assess fish populations.

About the lab

The Division’s Age and Growth lab processes samples for determining the age of fish. These samples include scales, ear bones called otoliths, opercula, and fin spines. The age data from these samples are used to better understand fish populations, which in turn assists in stock management.

Fish lay down marks (called annuli) every year on their hard parts just like a tree does. Counting these rings allows us to determine the age of the fish. Each species of fish grows a little differently and may lay down better looking annuli on one hard part than another (i.e. otoliths vs. scales). Read our Technical Report on the fish aging protocols used in the lab.

The lab regularly processes age structures from:

The lab was established and constructed in 2009. Funding for the lab is provided through the Wallop-Breaux amendments of the Sport Fish Restoration Act.

Additional Resources

Contact for Age and growth laboratory


DMF Staff Directory View 


(617) 727-3337


Gloucester Field Office
30 Emerson Avenue, Gloucester, MA 01930

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