Last modified on Jan 28, 2019
Prior to a season, readers familiarize themselves with current patterns by examining known-age samples collected that year. This gives personnel an opportunity to review new markings and patterns. Readers complete these examinations before age estimation begins. In locations where no known-age samples exist, readers review and test using the previous two years of samples and/or scales aged by multiple individuals.
Many locations conduct blind, independent reads of a subset of scales for each major species prior to production reading. If possible, this occurs as close to the beginning of production reading for a species as possible. For example, coho salmon samples are not collected until after mid-August so reviews occur in early August rather than in mid-May. The following process is recommended for pre-season review:
- Someone, usually Project Leader, chooses scale acetates for blind, independent readings.
- These are read independently by each reader assisting in production reading that year.
- Ages are entered and examined for differences by Project Leader.
- Readers and Project Leader examine scales where age estimations differed.
- Process is repeated until all readers reach >90% agreement.