The Alaska Fisheries Science Center website is now part of the NOAA Fisheries website.
Some information may not be up to date. Join us at our new location,
Please contact with any questions.

link to AFSC home page
Mobile users can use the Site Map to access the principal pages

link to AFSC home page link to NMFS home page link to NOAA home page

Age and Growth Program

Age Validation

Fish ages generated from interpreting growth rings on otoliths are validated and corroborated at the AFSC Age and Growth Program using a variety of techniques including lead/radium radiometrics, bomb carbon, and various other techniques. For a quick summary of age validation and age corroboration carried out by the AFSC Age and Growth Program please see the Species Aged table.

Age validation techniques
18O graph with otolith width=
Lead-radium decay chain
Mushroom cloud
  • Known Age
  • Year classes
  • Marginal Increment Analysis (MIA)
  • Mark and recapture



            | Home | Site Map | Contact Us | FOIA | Privacy | Disclaimer | | Accessibility | Print |           doc logo