Age validation of the first, second, and third annulus from the dorsal fin rays of lingcod (Ophiodon elongatus)

The first, second, and third annulus were identified in the dorsal fin rays of lingcod (Ophiodon elongatus). These annuli were validated as indicators of age by calculating the total radius of the fin rays of a lingcod that had completed one, two and three years of growth. Fish lengths came from known-age lingcod (from a rearing study and a year-round field sampling program) and modal progression studies. We measured the radii of the first, second, and third hyaline zone (0.36, 0.54, and 0.75 mm, respectively) from commercial and recreational catches of lingcod. The radii were significantly different among the three zones. Further, the radius of each zone corresponded to the total radius of the fin rays of known-age one-, two-, and three-year-old fish, validating them as true annuli. Thomas E. Laidig, Kelly R. Silberberg, and Peter B. Adams. "June 2001." System requirements: Adobe Acrobat Reader. Mode of access: World Wide Web. Includes bibliographical references (p. 15-19).