Ventral view
of red drum sagittal otoliths. Photo courtesy of GSMFC.
Lateral view
of red drum sagittal otoliths. Photo courtesy of GSMFC.
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Aging
of fish is most commonly accomplished by counting rings deposited
annually (annuli) on hard parts of a fish including: scales, otoliths
(ear bones), and spines. Fish age data is needed to properly assess
current abundance and potential recruitment to a fishery. Standardization
of ageing techniques is critical to the validity of age-based calculations
and is made especially important by the difficulty associated with
accurately and consistently identifying annuli. The Commission has
initiated a project to develop standard protocols for aging Commission-managed
species. Standards include the following:
- Determination
of the best hardpart to age a specific species of fish,
- Determination
of which rings represent a specific fish age,
- Development
of a reference collection to assist in training new agers, and
- Information
on use of fish ages in stock assessment models.
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