by

• Main Authors: R. Alpoim, E. Roman, B. Greene, R. Burry, W. R. Bowering
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2002
• Subjects: Canada; Greenland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.498.4930; http://archive.nafo.int/open/sc/2002/scr02-141.pdf

This Greenland halibut (Reinhardtius hippoglossoides) otolith exchange was carried out in order to examine for differences in age interpretations between Spain, Canada and Portugal. Statistical and graphical methods were used to evaluate differences in terms of bias and precision. In general, most differences in interpretations among age readers were within +/- 1-2 years although there were strong biases in several cases. The Spanish age reader had a tendency to assign lower ages to fish younger than 9 years old and higher ages to the older ones, relative to the Canadian age readers. The age reader from Portugal, like the Spanish age reader, assigned higher ages to the older fish (>8 years old) than Canada, but for the younger fish the agreement was very good. Burning the otoliths before reading seems to enhance the clarity in the last few annuli in older fish.