EPA's Vessel General Permit and Small Vessel General

Bocaccio resistance to depletion and recovery is also hindered by demographic features (Love et
al. 1998a). Bocaccio are long-lived fishes, taking several years to reach sexual maturity and
becoming more fecund with age (Dorn 2002). As harvesting targeted the largest individuals
available, bocaccio have become less capable of recovering population numbers (Love et al.
1998b). At present, in the complete absence of directed or bycatch fishing pressure, it is
estimated that bocaccio populations would have to have frequent good recruitment to restrain
their present decline (Tolimieri and Levin 2005). In addition, bocaccio reproduction appears to
be characterized by frequent recruitment failures, punctuated by occasional high success years
(Love et al. 1998b, MacCall and He 2002b). Over the past 30 years, 1977, 1984, and 1988 are
the only years in which recruitment appears to have been significant successes (it should be
noted that 1999 and 2002 also appear to have been strong, but survivorship into maturity is still
pending). Recruitment success appears to be linked to oceanographic/climactic patterns and may
be related to cyclic warm/cool ocean periods, with cool periods having greater success (Sakuma
and Ralston 1995, MacCall 1996, Love et al. 1998b, Moser et al. 2000b). Harvey et al. (2006a)
suggested that bocaccio may have recently diverted resources from reproduction, potentially
resulting in additional impairment to recovery. Overall, bocaccio have the highest variability of
recruitment of any rockfish studied to date, with recruitment exhibiting a random walk and high
temporal variability (MacCall and He 2002b, Tolimieri and Levin 2005).
Although population estimates are not available for the northern population, the southern
population has been estimated to number 1.6 million fish of 1 year of age or older in 2002
(MacCall 2002a). Of these, 1.0 million were estimated to occur south of Pt. Conception, where
recruitment has been stronger. However, individuals north of Pt. Conception tend to be larger
and, hence, more fecund. In 2002, the southern population was estimated to produce 720 billion
eggs annually (243 billion south of Pt. Conception). North of Pt. Conception, bocaccio are most
abundant in the Monterey Bay area, where prime habitat seems to be over the continental slope
and, secondarily, over the shelf (Dark et al. 1983).
The rate of decline for rockfish in Puget Sound has been estimated at ~3% annually for the
period 1965-2007. Various rebuilding estimates for bocaccio populations have predicted
recovery, but require long periods (98-170 years) and assume no mortality from fishing
(intentional harvests are closed, but bycatch still occurs)(MacCall and He 2002a, MacCall 2008,
NMFS 2008e).
Natural threats
Interspecies competition, predators, and climactic regimes are the primary natural factors that
depress bocaccio numbers. Copper and quillback rockfish may compete with bocaccio in Puget
Sound for available resources (NMFS 2008e). King salmon, lingcod, terns and other seabirds,
harbor seals, and Steller sea lions are known predators of bocaccio and other rockfish species
(Love et al. 2002, Beaudreau and Essington 2007, Lance and Jeffries 2007). Bocaccio and other
rockfish appear to be negatively influenced by El Niño conditions, possibly reducing available
prey supply (Moser et al. 2000a, Harvey 2005).
Anthropogenic threats
Although overfishing is the primary reason for bocaccio being proposed as a listed species,
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