90+ 



Female 



AGE (year) 



Figure 68. — Von Bertalanffy growth curves for male and female Greenland turbot, all areas, 1976 Bering Sea spring trawl survey (selected ages). Symbols 



indicate the mean length at each age. 



(Pereyra et al. see footnote 2). The distribution of biomass among 

 geographical regions was 89.2% in subareas 2 and 2 Slope (com- 

 bined) between St. George and Unimak Islands, and 10.8% in 

 subareas 3N, 3S, and 3 Slope (combined). 



The total number of individuals within the study area (available 

 to trawling) was estimated to be 149.2 million. In general, the 

 distribution of population numbers was similar to biomass except 

 in subareas 2 and 2 Slope due to differences in population size- 

 frequency distributions. 



Size composition. — Arrowtooth flounder taken during the 

 1976 spring survey ranged from 12 to 68 cm FL, with an overall 

 mean fork length of 27.9 cm (based upon 4,103 field 

 measurements; Fig. 70). In subarea 2, the size-frequency distri- 

 butions of male and female populations were sharply unimodal 

 and nearly symmetrical, with an overall mean fork length (sexes 

 combined) of 25.8 cm (range 12-50 cm). In subareas 2 Slope, a 



broad size range was observed (18-68 cm), and 62.1% of all in- 

 dividuals were > 30 cm FL. 



Age composition. — Estimates of age-frequency distribution 

 were made from an overall collection of 126 male and 257 female 

 saccular otoliths from areas B and D. The ranges in ages observed 

 were males, 3-8 yr; females, 3-12 yr. 



The apparent number of individuals within each age group of 

 the sampled population is summarized in Table 57. Although sub- 

 areas 3N and 3S are excluded because no length-frequency data 

 were collected, the estimates include 138.66 million (92.9%) of the 

 149.2 million individuals of the overall apparent population. 



Four-yr-old individuals were most abundant in all geographical 

 areas, accounting for 44-50% of the populations in each subarea 

 (Fig. 71). Overall (sexes combined), 83.0% of the total population 

 was aged 4 yr or less. Old individuals were most abundant in 



97 



