| Summary: | This study investigated the size-at-age (SAA) of Pacific halibut in the Gulf of Alaska and Bering Sea. In the past two decades, the size-at-age of halibut has undergone an extensive reduction. Observed SAA of Pacific halibut has changed substantially over time and the reasons behind changes in halibut SAA are not well understood. This project compared new and historical surface ages to demonstrate whether a differing degree of bias is present in surface ages made in earlier decades relative to those made today due to factors such as changes in surface age assignment protocol over time or quality of microscopes used. Data are presented as fifteen CSV files: Decadal re-aging: NPRB_1309_1_decadal_reaging_data.csv Otolith and maturity codes: NPRB_1309_1_decadal_reaging_codes.csv NPRB_1309_1_individual_increment_codes.csv Increment data includes one CSV file for each cohort (1977, 1987, 1992, 2002) and IPHC Regulatory Area (2B, 3A and 4D): NPRB_1309_1_individual_increment_data_2B_1977.csv NPRB_1309_1_individual_increment_data_3A_1977.csv NPRB_1309_1_individual_increment_data_4D_1977.csv NPRB_1309_1_individual_increment_data_4D_1987.csv NPRB_1309_1_individual_increment_data_3A_1987.csv NPRB_1309_1_individual_increment_data_2B_1987.csv NPRB_1309_1_individual_increment_data_3A_1992.csv NPRB_1309_1_individual_increment_data_2B_1992.csv NPRB_1309_1_individual_increment_data_4D_1992.csv NPRB_1309_1_individual_increment_data_2B_2002.csv NPRB_1309_1_individual_increment_data_3A_2002.csv NPRB_1309_1_individual_increment_data_4D_2002.csv
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