
Tanner Crab
The Council reviewed a discussion paper on nonpelagic trawl and pot cod effort and observer coverage in two ADF&G statistical areas around Kodiak Island as well as in Chiniak Gulley (see Figure), and chose to take no further action. The discussion paper was a targeted follow up to a 2017 discussion paper on the protections afforded to Tanner crab in the Central Gulf of Alaska (CGOA), given concerns about whether the recovery of Tanner crab in the CGOA is constrained by mortality associated with groundfish fisheries. Tanner crab in the CGOA are under State management, and the distribution of Tanner crab overlaps, in part, with the Federally-managed CGOA groundfish fisheries. The 2017 paper concluded that the factors constraining Tanner crab stock recovery in the CGOA are complicated and are likely to include multiple environmental factors whose relative impact is not well understood.
The discussion paper showed that nonpelagic trawl and pot cod effort has generally declined since 2011-2012 in the statistical areas of concern. A possible exception is the arrowtooth flounder trawl fishery that appears to have increased effort in 2016 and 2017. Effort in those years, as measured in the discussion paper, was greater than in all years except 2011. Nevertheless, the variation in Tanner crab PSC in groundfish fisheries appears to be most strongly related to the ADF&G estimates of Tanner crab abundance, rather than fishery effort.
The paper also reported on observer coverage. Observer coverage in the areas of concern has been proportional to coverage in other areas in the CGOA. While it was discussed at the meeting whether to consider increasing observer coverage in these statistical areas, such an action would negatively impact observer coverage in the GOA as a whole, and would also upset the statistical basis for the deployment of observers.
The Council chose to take no further action on this issue at this time. Developing an electronic monitoring program for trawl CVs in the CGOA, which is a Council objective underway through the Trawl EM Committee, should help improve the precision of current Tanner PSC estimates, and also assist in determining if observer effects are a consideration for this issue. Staff contact is Jim Armstrong.