Science & Data

Because of the 2013 government shutdown, there was insufficient time to present alternate model configurations or new analyses, and some sections may not be fully updated. Relative to last year’s assessment, we made the following substantive changes in the current assessment. Input data: New data included in the assessment model were relative abundance and length data from the 2013 longline survey, relative abundance and length data from the 2012 longline and trawl fisheries, age data from the 2012 longline survey and 2012 fixed gear fishery, abundance and length data from the 2013 Gulf of Alaska trawl survey, updated 2012 catch, and projected 2013 catch.

In 2005, BSAI rockfish were moved to a biennial assessment schedule to coincide with the frequency of trawl surveys in the Aleutian Islands (AI) and the eastern Bering Sea (EBS) slope. These surveys occur in even years and for these years a full assessment of Pacific ocean perch (POP) in the BSAI area is conducted. The 2012 full assessment can be found at http://www.afsc.noaa.gov/REFM/docs/2012/BSAIpop.pdf. In years without a scheduled Aleutian Islands survey, an “update” is produced by revising the recent catch data and re-running the projection model using the results from the previous full assessment as a starting point. Therefore, this update does not incorporate any changes to the 2012 assessment methodology or input data, but does include updated catch estimates for 2012-2014.

The Bering Sea/Aleutian Islands (BSAI) Other rockfish complex includes all species of Sebastes and Sebastolobus, except for Pacific ocean perch (POP, Sebastes alutus), northern rockfish (Sebastes polyspinis), dark rockfish (Sebastes ciliatus), rougheye rockfish (Sebastes aleutianus), blackspotted rockfish (Sebastes melanostictus) and shortraker rockfish (Sebastes borealis). In 2013, species caught in the BSAI in the “other species” complex included black rockfish (Sebastes melanops), redbanded rockfish (Sebastes babcocki), darkblotched rockfish (Sebastes crameri), yelloweye rockfish (Sebastes ruberrimus), harlequin rockfish (Sebastes variegatus), redstripe rockfish (Sebastes proriger), dusky rockfish (Sebastes variabilis; formerly light dusky), thornyhead (Sebastolobus alascanus), and longspine thornyhead (Sebastolobus altivelis). Many of the species in the genus Sebastes are relatively uncommon; and different species may be represented in different years. Between 2004-2013, this category has consisted primarily of dusky rockfish and shortspine thornyhead.

The Bering Sea/Aleutian Islands “other flatfish” group have typically included those flatfish besides northern rock sole, yellowfin sole, arrowtooth flounder, Kamchatka flounder and Greenland turbot. Flathead sole (Hippoglossoides elassodon) were part of the other flatfish complex until they were removed in 1995, and Alaska plaice was removed from the complex in 2002, as sufficient biological data exists for these species to construct age-structured population models. In contrast, survey biomass estimates are the principal data source used to assess the remaining other flatfish. Although over a dozen species of flatfish are found in the BSAI area, the other flatfish biomass consists primarily of starry flounder, rex sole, longhead dab, Dover sole and butter sole. A full list of the species in the other flatfish complex are shown in Table 11.1. At present, no evidence of stock structure is evident for these species in the Bering Sea/Aleutian Islands region, although no formal genetic or tagging study has been conducted on these species in this region.

Through 2010, octopuses were managed as part of the BSAI “other species” complex, along with sharks, skates, and sculpins. Historically, catches of the other species complex were well below TAC and retention of other species was small. Due to increasing market values, retention of some other species complex members is increasing. Beginning in 2011, the BSAI fisheries management plan was amended to provide separate management for sharks, skates, sculpins, and octopus and set separate catch limits for each species group. Catch limits for octopus for 2011 were set using Tier 6 methods based on the maximum historical incidental catch rate. For 2012 and 2013, a new methodology based on consumption of octopus by Pacific cod was introduced; this method is also recommended for 2014 and 2015. The consumption estimate has not been revised from 2012; the authors recommend that this calculation be revisited once every five years.

In 2005, BSAI rockfish were moved to a biennial assessment schedule to coincide with the frequency of trawl surveys in the Aleutian Islands (AI) and the eastern Bering Sea (EBS) slope. These surveys occur in even years and for these years a full assessment of northern rockfish in the BSAI area will be conducted. The 2012 full assessment can be found at http://www.afsc.noaa.gov/REFM/docs/2012/BSAInorthern.pdf. In years without a scheduled Aleutian Islands survey, an “update” is produced by revising the recent catch data and re-running the projection model using the results from the previous full assessment as a starting point. Therefore, this update does not incorporate any changes to the 2012 assessment methodology or input data, but does include updated catch estimates for 2012-2014.

In 2005, BSAI rockfish were moved to a biennial assessment schedule to coincide with the frequency of trawl surveys in the Aleutian Islands (AI) and the eastern Bering Sea (EBS) slope. These surveys occur in even years and for these years a full assessment of northern rockfish in the BSAI area will be conducted. The 2012 full assessment can be found at http://www.afsc.noaa.gov/REFM/docs/2012/BSAInorthern.pdf. In years without a scheduled Aleutian Islands survey, an “update” is produced by revising the recent catch data and re-running the projection model using the results from the previous full assessment as a starting point. Therefore, this update does not incorporate any changes to the 2012 assessment methodology or input data, but does include updated catch estimates for 2012-2014.

Kamchatka flounder are assessed on an annual basis in the Bering Sea/Aleutian Islands region to coincide with the annual eastern Bering Sea (EBS) multispecies groundfish trawl survey conducted each summer and also the biennial Bering Sea slope and Aleutian Islands surveys. Due to a temporary lapse in appropriations, the Federal Government implemented a shutdown from October 1 – October 16, 2013. Although the EBS shelf survey was completed in 2013, the shutdown did not allow time to produce a full stock assessment for Kamchatka flounder and many other species. Therefore, an executive summary is presented to provide management recommendations for the 2014 fishing season

Grenadiers are presently considered “nonspecified” by the NPFMC, which means they are technically not part of the NPFMC management process and are not assigned values for overfishing levels (OFL), acceptable biological catch (ABC), or total allowable catch (TAC). Therefore, there are no limitations on catch or retention, no reporting requirements, and no official tracking of grenadier catch by management. However, at the June, 2012 NPFMC meeting a motion was passed that included a purpose and need statement for moving grenadiers into the FMPs and four alternatives for doing so. An Environmental Assessment/ Regulatory Impact Review/ Initial Regulatory Flexibility Analysis (EA/RIR/IRFA) for the proposed FMP amendments will be presented at the December, 2013 meeting with final action scheduled for February, 2014.

Due to the October government shutdown model exploration, this year was limited. We present the reference model from last year updated with the most recent data and one alternative model which include autocorrelation in the recruitment deviations. The stock continues to be modeled using the same software as previous assessments (Stock Synthesis 3). Our reference model this year, Model 1, has the same configuration as last year’s Reference Model (2012 Model 2) and was used for all projections and specifications, Model 2 (last year’s Model 3) is presented only for comparisons.