Purpose and Need

The purpose of this amendment was to establish a plan to rebuild stocks of Pacific ocean perch (POP) (Sebastes alutus), a type of rockfish, in the GOA. POP is a highly-valued groundfish. It was heavily exploited by a foreign trawl fleet from the early 1960's until the mid-1970's. Thereafter, a domestic at-sea processing fleet harvested POP at a substantially lower rate. Catches of POP peaked in 1965 when an estimated 350,000 metric tons (mt) were harvested by the foreign fleet; catches declined sharply in the late 1960's. From 1961-1977, annual POP landings averaged over 40,000 mt; after 1977, landings averaged 6,000 mt. In the domestic fishery, POP was managed as part of a larger slope rockfish assemblage of about 20 species until 1991, when POP was established as a separate target species category to prevent possible overfishing. Prior to Amendment 32, overfishing levels had been defined GOA-wide. As a result of increased concern about the status of POP stocks, biomass assessment methodology has been improved and domestic harvest levels have been reduced. The 1993 total allowable catch (TAC) of 2,560 mt was available only as incidental bycatch in other groundfish fisheries. In recent years, POP has been managed as a single species, harvest levels have been reduced, and directed fisheries have been restricted or eliminated. The intent of this amendment was to minimize POP mortality necessary to maximize the probability of rebuilding success in a realistic time period.

Analysis

An 86-page EA/RIR/IRFA (Secretarial review draft dated November 8, 1993) was prepared for this amendment. Four alternatives including the status quo were considered. The other alternatives would have established a slower rebuilding schedule (11 years) via an optimal fishing mortality rate or a faster schedule (18 years) by prohibiting a directed fishery for POP. The alternative chosen was a fishing mortality rate that was intermediate between the optimal rate and a bycatch only rate.

Regulation Summary

Amendment 32 established a rebuilding plan for POP. The alternative chosen was projected in modeling simulations to rebuild POP biomass to a target level (BMSY) in about 14 years by harvesting POP at a fishing mortality rate lower than the optimum rate. The amendment stated that “stocks will be considered to be rebuilt when the total biomass of mature females is equal to or greater than BMSY”. Under Amendment 32, the overfishing level would be distributed among the eastern, central, and western areas in the same proportions as POP biomass occurs in those areas. This measure would avoid localized depletion of POP and would rebuild POP at equal rates in all regulatory areas of the GOA. The optimal fishing mortality rate is the rate that maximizes expected biological and economic yields over a range of plausible stock-recruitment relationships.

Amendment 32 established the procedure for deriving the annual GOA TACs for POP. Annual TACs will be established as follows:

1) determine the current biomass, BMSY, and the optimal fishing mortality rate;   

2) determine the fishing mortality rate halfway between the optimal fishing mortality rate and the fishing mortality rate estimated to be sufficient to supply unavoidable bycatch of POP based on 1992 bycatch rates; 

3) when the current biomass of mature females is less than BMSY, adjust the resultant fishing mortality rate in (b) by the ratio of current biomass to BMSY. When BMSY is attained, the fishing mortality rate will be the optimal fishing mortality rate; 

4) the GOA TAC of POP is the amount of fish resulting from the adjusted fishing mortality rate in (c); and 

5) the TAC is apportioned among regulatory areas in proportion to POP biomass distribution.

Results

In 1996, two years after the rebuilding plan was established, Amendment 38 was implemented to allow the POP TAC to be set at or below the amount dictated by the rebuilding plan’s algorithm. Amendment 41, which took effect in 2000, prohibited trawling in the Eastern area east of 140 degrees W. longitude. Since 1994, the spawning stock biomass has increased due to good recruitment and low fishing mortality. The rebuilding plan required that female spawning biomass be greater than Bmsy, and the stock was considered rebuilt in 1996. Amendment 68, which was implemented in 2006, implemented the Central GOA Rockfish Pilot Program (RPP). The intention of this program was to enhance resource conservation and improve economic efficiency for harvesters and processors in the rockfish fishery. The RPP was renewed in 2011 under Amendment 88.

According to the 2017 stock assessment, the original rationale for area-specific OFLs from the rebuilding plan no longer exists because the overall population is above target levels and is less vulnerable to occasional overages. Therefore, in terms of rebuilding the stock, management area OFLs are no longer a necessity for the GOA POP stock. The projected female spawning biomass for 2019 = 176,934 mt, well above B35% (102,767 mt).