2019 Assessment of the Sablefish Stock in Alaska

The longline survey abundance index increased 47 percent from 2018 to 2019 following a 14 percent increase in 2018 from 2017. The lowest point of the time series was 2015. The fishery catch-rate/abundance index stayed level from 2017 to 2018 and is at the time series low (the 2019 data are not available yet). Spawning biomass is projected to increase rapidly from 2020–2022, and then stabilize.

Sablefish are managed under Tier 3 of NPFMC harvest rules. Reference points are calculated using recruitments from 1977–2015. The updated point estimate of B40 percent, is 105,976 t. Since projected female spawning biomass (combined areas) for 2020 is 113,368 t (7 percent higher than B40 percent, or B43 percent), sablefish is in sub-tier “a” of Tier 3. The updated point estimates of F40 percent, and F35 percent from this assessment are 0.102 and 0.121, respectively. Thus, the maximum permissible value of FABC under Tier 3a is 0.102, which translates into a 2020 ABC (combined areas) of 44,065 t. The adjusted OFL fishing mortality rate is 0.121, which translates into a 2020 OFL (combined areas) of 51,726 t. An important consideration is that these reference points do no yet include the 2016 year class and next year. When the 2016 year class enters the recruitment time series, relative stock status will decline because the B40 percent reference point will increase substantially. Model projections indicate that this stock is not subject to overfishing, not overfished, nor approaching an overfished condition.