00000nam 2200000zi 4500 9.950448 CaOODSP 20250528082309 m o d f cr mn||||||||| 250425e198208##bccab ob f000 0 eng d CaOODSP eng rda CaOODSP eng eng fre n-cn-bc pn----- x7x8 Fs97-4/1670E-PDF Fs97-4/1670 Westrheim, S. J., author. Progress report on validating age determination methods for Pacific cod (Gadus macrocephalus) / by S.J. Westrheim and W. Shaw. Nanaimo, British Columbia : Department of Fisheries and Oceans, Resource Services Branch, Pacific Biological Station, August 1982. ©1982 1 online resource (iii, 41 pages) : illustrations, map. text txt rdacontent computer c rdamedia online resource cr rdacarrier Canadian manuscript report of fisheries and aquatic sciences, 0706-6473 ; no. 1670 Digitized edition from print [produced by Department of Fisheries and Oceans]. Includes bibliographical references (pages 10-11). "Past attempts at validating age determination of Pacific cod (Gadus macrocephalus) are reviewed. Results of an improved scale-reading technique and exploratory techniques with dorsal and pectoral fin rays are presented. Among-reader consistency for both scales and fin rays was poor over the age range, except for age 0. Accuracy of scale readings was 100% at age 1, 91% at age 2, and 88% at age 3, based on scales collected from 96 known-age cod. Further studies are recommended. Fin-ray ages were older than scale ages, for the same fish, and the deviations varied inversely with scale age"--Abstract, page iii. Includes abstracts in English and French. Pacific cod Age determination British Columbia Pacific Coast. Pacific cod British Columbia Pacific Coast Growth. Morue du Pacifique Âge Détermination Colombie-Britannique Pacifique, Côte du. Morue du Pacifique Colombie-Britannique Pacifique, Côte du Croissance. Canada. Department of Fisheries and Oceans, issuing body. Pacific Biological Station (1972- ), issuing body. Canadian manuscript report of fisheries and aquatic sciences ; no. 1670. (CaOODSP)9.505211 PDF 959 KB https://publications.gc.ca/collections/collection_2025/mpo-dfo/fs97-4/Fs97-4-1670-eng.pdf