Aging for Fisheries Management

Developed in 2001, the Chippewas of Nawash Calcified Structure Analysis Facility (CNCSAF) is rapidly evolving and making local advances in the field of fish age estimation. The facility is now fully capable of production scale and otolith age estimation using advanced digital imaging and analysis techniques. Operational protocols were developed on the basis of adaptive management with the following mandate, goals and objectives in mind.

Mandate: Rigorous scientific study of fish calcified structures for the purpose of quantifying and validating fish age and for analysing calcified structure growth patterns as they relate to somatic (body) growth.

Goal: Provide Chief and Council with accurate age estimates that have been thoroughly validated and based on the best available techniques.



  1. Increase managers confidence in age estimates to the point where they can be incorporated into age-based population models.
  2. Application of the principles of adaptive management, specifically alternative hypotheses and the testing of apriori predictions generated from these hypotheses to the field of fish age estimation.
  3. Validation of age estimation techniques and procedures.
  4. Minimization of sampling error and biases.
  5. Development of the tools necessary for advances in the field of fish age estimation, particularly digital image analysis.
  6. Develop known-age digital reference collections for Lake Huron bloater chub and lake whitefish.
  7. Strict adherence to the principles of quality control.
  8. Maintenance of scientific rigor and transparency of our work through web-based open forum and peer review.

Program Description: The process of age estimation involves the interpretation and counting of growth zones in or on fish calcified structures