Purpose and Need

The Bering Sea Tanner crab (C. bairdi) stock was measured to be at near historically low levels, based on NMFS bottom trawl survey data. The fishery was also in trouble. The 1995 Tanner crab season produced only 4.5 million lb (2017 mt) for the 196 vessels participating. This amount was the lowest catch since the fishery reopened in 1988. Preliminary 1996 survey data indicated that the stock decline would continue. Tanner crab PSC limits for trawl fisheries established under Amendment 10 were 1,000,000 crab in Zone 1 and 3,000,000 crab in Zone 2. The objective of this amendment was to reduce Tanner crab bycatch in trawl fisheries, particularly at low stock sizes, to assist in recovery of this stock.

Analysis

A 41-page EA/RIR/IRFA (final draft dated November 20, 1996) was prepared for this amendment. Three alternatives including the status quo were considered. The other alternative that was not chosen would have reduced the PSC limits to a fixed level regardless of stock size (900,000 crab in Zone 1 and up to 2,100,000 crab in Zone 2). The alternative chosen was more conservative in that defining a larger area may offer more protection.

Regulation Summary

The alternative adopted and approved under Amendment 41 provides for the annual specification of the revised PSC limits based on the total estimated abundance of C. bairdi as shown in the figure below. C. bairdi taken as bycatch within the zones accrue towards the PSC limits established for individual trawl fisheries. Upon attainment of a PSC limit apportioned to a particular trawl target fishery, that fishery is prohibited from fishing within the specified zone. Note that in 1998, the Council adopted a provision to reduce opilio crab bycatch by an additional 50,000 C. bairdi crab as part of the regulation prohibiting the use of bottom trawl gear for pollock fisheries.

Results

Since the amendment was approved, bycatch of Tanner crab was been reduced. Nevertheless, the Tanner crab stock continued to decline, and was deemed “overfished” on March 3, 1999 because the survey estimate of spawning stock biomass fell below the minimum spawning stock threshold established for this crab stock. In October 1999, the Council adopted a rebuilding plan for this stock, but determined that bycatch limits established under Amendment 41 were sufficiently conservative.