2000. Calculation of Catch-at-Age for Commercially Caught Greenland Halibut

• Main Authors: W. R. Bowering, W. B. Brodie
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Greenland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.614.9606; http://archive.nafo.int/open/sc/2000/scr00-024.pdf

Catch-at-age data from the commercial Greenland halibut fishery in NAFO Subarea 2 and Divisions 3KLMNO have been calculated annually since 1975. However, the data have been incomplete since 1989 due to uncertainty in the yearly catches in the NAFO Regulatory Area (NRA) and lack of ageing data. Catch-at-age data from the Canadian portion of the fishery have been available annually from 1975-97 and are updated here for 1998 and 1999. This paper will describe how annual ageing data from the Canadian fishery were used in combination with annual length frequency data from other countries, primarily Spain and Portugal, fishing Greenland halibut in the NRA to compute catch-at-age from 1989-99. Where data were lacking from other countries their catches were generally adjusted by the combined catch-at-age of Spain and Portugal. Although total annual catches remain uncertain for many years, the computations were based on best estimates as agreed at the yearly June assessment meetings of the NAFO Scientific Council.