Northeast Fisheries Science Center Reference Document 07-06
The 2005 Assessment of Acadian Redfish, Sebastes fasciatus Storer, in the Gulf of Maine/Georges Bank Region
by Ralph K. Mayo1, Jon K.T. Brodziak, John M. Burnett, Michele L. Traver, and Laurel A. Col
1National
Marine Fisheries Serv., Woods Hole Lab., 166 Water St., Woods Hole MA
02543-1026
2National
Marine Fisheries Serv., 2570 Dole St., Honolulu HI 96822-2396
Print
publication date April 2007;
web version posted April 26, 2007
Citation: Mayo RK, Brodziak JKT, Burnett JM, Traver ML, Col LA.
2007. The 2005 Assessment of Acadian redfish, Sebastes fasciatus Storer, in the Gulf of Maine/Georges Bank region. US Dep Commer, Northeast
Fish Sci Cent Ref Doc 07-06; 32 p.
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ABSTRACT:
A comprehensive analysis of the
stock dynamics of Acadian redfish (Sebastes fasciatus Storer) in the
Gulf of Maine/Georges Bank region off the Northeast coast of the United States
between 1934 and 2004 is presented. The status
of the Gulf of Maine/Georges Bank Acadian redfish stock is provided, and estimates
of fishing mortality and spawning stock biomass in 2004 are provided. Precision estimates of the 2004 fishing
mortality and spawning stock biomass estimates are also given. This assessment updates the analyses in the 2001
assessment of the Gulf of Maine/Georges Bank Acadian redfish stock reviewed at the
33rd Northeast Regional Stock Assessment Workshop (SAW 33) (NEFSC 2001b; Mayo et
al. 2002). The analyses presented
herein were recently reviewed at the 2005 Groundfish Assessment Review Meeting
(GARM) (NEFSC 2005).
The 2005 assessment is based on
several sources of information, including: (a) the age composition of USA 1969–1985
commercial landings; (b) Northeast Fisheries Science Center spring and autumn
research vessel survey data; and (c) standardized USA commercial fishing effort
data. Information on total landings is
available since the inception of the fishery in the mid 1930s, and a measure of
commercial catch per unit of effort was derived for most of the period when the
directed fishery operated (1942–1989). Trends in total biomass and exploitable biomass are illustrated, and
additional information on the age structure of the stock is presented,
including the age composition of the commercial landings (1969–1985) and an
index of the age composition of the stock based on research vessel survey data
(1975–2004). Fishery-dependent and fishery-independent
information are integrated using an age-structured biomass dynamics model to generate
estimates of instantaneous fishing mortality, stock biomass, and recruitment on
an annual basis from 1934 through 2004.
Acadian redfish have supported a
substantial domestic fishery in the Gulf of Maine and the Georges Bank (Great
South Channel) regions off the northeast coast of the United States (Northwest
Atlantic Fisheries Organization [NAFO] Subarea 5) since the 1930s, when the
development of freezing techniques enabled a widespread distribution of the
frozen product throughout the country. Landings
rose rapidly from less than 100 metric tons (mt) in the early 1930s to over
20,000 mt in 1936, peaked at 56,000 mt in 1942, then declined throughout the
1940s and 1950s. Landings from the Gulf
of Maine increased during the 1970s, but have been declining throughout the
1980s and 1990s. Since the mid 1990s, landings
from this stock have remained at their lowest level since the directed fishery
commenced in the 1930s.
Fishing mortality
in 2004 is estimated at 0.00239, a substantial decline from 2001. Spawning stock biomass increased from 124,400
mt in 2001 to 175,800 mt in 2004. The
estimate of the 2000 spawning stock biomass based on the present assessment is
within 5% of the estimate obtained from the 2001 assessment.
Spawning stock
biomass in 2004 was 175,800 mt, 74% of SSBMSY (236,700 mt) and F in 2004
is estimated at 0.002, well below FMSY (0.04). Thus, the stock is not overfished and
overfishing is not occurring.
INTRODUCTION
Three species of Sebastes are common in the Northwest
Atlantic. The Acadian redfish, S.
fasciatus Storer (Robins et al. 1991a), and the deepwater redfish, S. mentella Travin, are virtually
indistinguishable from each other based on external characteristics. Both species are considered beaked redfish based
on the presence of a prominent symphyseal tubercle on the anterior mandible
(Klein-MacPhee and Collette 2002). The
third species, the golden redfish, S. norvegicus Ascanius (formerly S.
marinus; see Robins et al. 1991b) can be distinguished from the
beaked redfishes based on external characteristics, notably a greatly
diminished symphyseal tubercle.
Visual separation of Acadian redfish
and deepwater redfish can be accomplished reliably by counting the number of soft
rays in the anal fin (Ni 1982) and internal examination of the passage of the
extrinsic gas bladder musculature between the second, third, and fourth ventral
ribs (Ni 1981; see Hallacher 1974). The two species can also be distinguished
genetically by the genotype at the malate dehydrogenase locus (MDH-A*)
(Payne and Ni 1982; McGlade et al. 1983). In general, deepwater redfish are predominant
in the northernmost reaches of the Northwest Atlantic, extending from the Gulf
of St. Lawrence and the Grand Banks of Newfoundland across the North Atlantic
to European waters. (See Atkinson 1987
for a general review.) Acadian redfish
and deepwater redfish co-occur in the Gulf of St. Lawrence and the Laurentian
Channel, where introgressive hybridization occurs between the two species
(Roques et al. 2001), and on the
Grand Banks and the Flemish Cap. Morphometric
studies have shown that within the Gulf of St. Lawrence, deepwater redfish have
a more fusiform body shape than Acadian redfish (Valentin et al. 2002). Deepwater
redfish are less prominent in the more southerly regions of the Scotian Shelf and
appear to be virtually absent from the Gulf of Maine, where Acadian redfish
appear to be the sole representative of the genus Sebastes (Sevigny et al. 2003).
Acadian redfish are long-lived,
exhibit ovoviviparous reproduction, and are characterized by low fecundity and a
low natural mortality rate. The testes
of the males ripen in the autumn and mating occurs in late autumn and early
winter (Kelly
and Wolf 1959; Pikanowski et al. 1999). Fertilization of
the ripe eggs is delayed until spring and larval extrusion generally occurs
from late spring through July and August, as incubation requires between 45 and
60 days (Kelly et al. 1972;
Kelly and Wolf 1959). Generally, between 15,000 and 20,000 extruded larvae are produced per
female during each spawning cycle (Kelly et al. 1972).
Acadian redfish have supported a
substantial domestic fishery in the Gulf of Maine and the Georges Bank (Great
South Channel) regions off the northeast coast of the United States (Northwest
Atlantic Fisheries Organization [NAFO] Subarea 5) since the 1930s, when the
development of freezing techniques enabled a widespread distribution of the
frozen product throughout the country. Landings
rose rapidly from less than 100 metric tons (mt) in the early 1930s to over
20,000 mt in 1936, peaked at 56,000 mt in 1942, then declined throughout the 1940s and 1950s (Table 1, Figure 1). As landings declined in local waters, fishing
effort began to expand to the Scotian Shelf and the Gulf of St. Lawrence (NAFO
Subarea 4), and finally to the Grand Banks of Newfoundland (NAFO Subarea 3). This expansion continued throughout the 1940s
and early 1950s, culminating in a peak USA catch of 130,000 mt in 1952. By the mid 1950s, redfish stocks throughout
the Northwest Atlantic were heavily exploited (Atkinson 1987), and total
landings began to decline in all Subareas. Landings from the Gulf of Maine increased temporarily during the 1970s,
but have been declining throughout the 1980s and 1990s. Since the mid 1990s, landings from this stock
have remained at their lowest level since the directed fishery commenced in the
1930s.
United States commercial fisheries
for Acadian redfish are managed under the New England Fishery Management
Council's Northeast Multispecies Fishery Management Plan (FMP). Under this FMP, redfish are included in a
complex of 15 groundfish species managed by time/area closures, gear restrictions,
minimum size limits, and – since 1994 – by direct effort controls including a
moratorium on permits and days-at-sea restrictions under Amendments 5, 7, and
13 to the FMP. Amendment 9 established initial biomass rebuilding targets (Anon.
1998) and defined control rules which specify target fishing mortality rates
and corresponding rebuilding time horizons. Amendment 13 implemented formal rebuilding plans within specified time
frames based on revised biomass and fishing mortality targets derived by the Working Group on
Re-evaluation of Biological Reference Points for New England Groundfish (NEFSC
2002b). The
goal of the management program is to reduce fishing mortality to levels which
will allow stocks within the complex to initially rebuild above minimum biomass
thresholds, then to attain and remain at or near target biomass levels.
The dynamics of this stock have been
evaluated using a variety of techniques including production models (Schaefer 1954, 1957;
Pella and Tomlinson 1969; Fox 1975), yield per
recruit (Thompson and Bell 1934; Beverton and Holt 1957), and virtual population analysis (VPA). A preliminary production model estimate
suggested a long-term potential yield of between 14,000 and 20,000 mt,
depending on model formulation (Mayo 1975, 1980). A yield per recruit analysis performed with
M=0.05 and a partial recruitment of 50% at age 6 and full recruitment at ages 9
and older indicated FMAX at 0.13 and F0.1 at 0.06 (Mayo
1993). VPA, which was first performed on
this stock using catch at age data from 1969–1980, indicated that age 9+
fishing mortality rates (in the range of 0.18 to 0.28 throughout most of the
1970s) were accompanied by a 62% decline in exploitable biomass (ages 5+)
between 1969 and 1980 (Mayo et al. 1983). A subsequent analysis which included
additional catch at age data through 1983 indicated that, although F had begun
to decline from a maximum value of 0.28 in 1979 to 0.17 in 1983, exploitable
biomass had been reduced by 75% from the 1969 level by 1984 (NEFC 1986). The VPA was discontinued after 1986, but
further declines in redfish landings since then suggest that F is now likely to
be rather low (at or below M), rendering the convergence of VPAs unlikely.
An index-based assessment of this
stock was presented at the 15th Northeast Regional Stock Assessment Workshop (SAW)
in December 1992 (Mayo 1993; NEFSC 1993a, 1993b) and an interim assessment
was reviewed by the Northern/Southern Demersal Working Group in August 2000
(NEFSC 2001a). However, the index-based
results were not relevant to the then existing biological reference points (see
Anon. 1998). The initial peer review of
an age-based dynamics model assessment for this stock (Mayo et al. 2002) occurred at the 33rd
Northeast Regional SAW in June 2001 (NEFSC 2001b), and an updated index
assessment was reviewed at the Groundfish Assessment Review Meeting (GARM) in
October 2002 (NEFSC 2002a; Mayo and Col 2002). The present age-based dynamics model assessment was reviewed at the
second GARM in August 2005 (NEFSC 2005; Mayo et al. 2005).
The potential for Acadian redfish to
return to conditions observed in the 1960s is limited in part by their
combination of slow growth and low fecundity. Even at relatively low levels of F (0.03–0.05), restoration of the 1969
age structure is not likely to occur except under extremely favorable
recruitment conditions over several decades (Mayo 1987). The recent appearance of just such favorable
recruitment during the past decade suggests that restoration of age structure
is underway.
THE FISHERY
Trends in Catch and Effort
Landings of Acadian redfish from
Subarea 5 from 1934 through 2004 are given in Table 1 and illustrated in Figure 1. This fishery has been prosecuted
almost exclusively by large (>150 gross registered tons) otter trawlers
fishing out of Maine and Massachusetts ports. Landings by domestic vessels rose rapidly from less than 100 mt in the
early 1930s to over 20,000 mt in 1936, peaked at 56,000 mt in 1942, then
declined throughout the 1940s and 1950s. Although Acadian redfish have been harvested primarily by domestic
vessels, distant water fleets took considerable quantities for a brief period
during the early 1970s (Table 1, Figure 1), at times accounting for 25-30% of
the total Subarea 5 redfish catch. The
distant water fleet effort, combined with increased domestic fishing effort,
resulted in a brief increase in total catch to about 20,000 mt during the early
1970s. With the declaration of exclusive
economic zones (EEZ) by the USA and Canada in 1977, USA vessels could no longer
access redfish stocks on the Scotian Shelf and the Grand Banks. The fishery for Acadian redfish was then
restricted almost exclusively to the Gulf of Maine except for a small portion
of the Scotian Shelf off Southwest Nova Scotia. Landings from the Gulf of Maine increased temporarily during the late
1970s, but declined throughout the 1980s and have averaged less than 500 mt per
year during the 1990s and the early part of the 21st century.
Commercial catch per unit effort
(CPUE) indices from 1942–1989 for directed redfish trips, standardized by
vessel tonnage class as described by Mayo et al. (1979), are listed in Table 1 and illustrated in Figure 2. The
resulting calculated fishing effort values were derived by dividing total
annual landings by the directed CPUE index. Directed CPUE has declined steadily from about 6 tons per standard day
fished during the late 1960s to less than 2 tons per day fished after 1980
(Table 1, Figure 2). This decline is
consistent with the 60–70% decline in exploitable biomass estimated by previous
VPAs (Mayo et al. 1983; NEFC 1986). Total fishing effort, after nearly tripling between 1969 and 1979
(coincident with the highest estimates of fishing mortality [NEFC 1986]),
appeared to stabilize during the mid 1980s before declining markedly through
1989.
Traditionally, the directed fishery
for redfish in the Gulf of Maine was prosecuted by vessels using otter trawls
with relatively small mesh in the range of 70–80 mm. After the 1980s, under domestic management
plans, minimum mesh size regulations were imposed on vessels fishing for the
major demersal species off the New England coast, including Acadian
redfish. In 1977, following
implementation of the Magnuson
Fishery Conservation and Management Act, the minimum
allowable mesh size increased from 114 to 130 mm; by 1994 the minimum mesh size
had increased to 152 mm. These mesh
restrictions, combined with low biomass and truncated size and age structure of
the redfish stock, have effectively eliminated the prosecution of a fishery
since the mid 1980s.
Age Composition of the 1969–1985 Landings
Estimates of the number of fish
landed at age were derived from biological sampling data collected in the ports
during the period 1969 through 1985 (Table 2, Figure 3). With the sharp decline in landings during the
1980s, ageing of commercial samples was discontinued after 1985. For the period 1969–1985, however, estimates
of numbers landed at age were derived by applying quarterly age/length keys,
separately by sex, to the estimated numbers landed at length by sex. The overall age composition was then obtained
by addition of the estimates by sex.
Landings at age and mean weight at
age matrices based on all available commercial length and age data from 1969
through 1985 are given in Table 3. The
sharp discontinuity in the age structure of the population created by infrequent
recruitment after the 1960s can be inferred from the age composition of the
landings; this is in contrast to a more uniform age structure in the 1970s
resulting from a series of moderate year classes produced in the 1950s and
1960s. The most striking feature is the
singular presence of the 1971 year class advancing through the fishery since
1976, followed by the entrance of the 1978 year class during 1983–1985. By the early 1980s the fishery had become
dependent on a few relatively strong year classes and recruitment appeared to
have diminished considerably.
BOTTOM TRAWL SURVEY RESULTS
Bottom trawl surveys have been
conducted by the Northeast Fisheries Science Center (NEFSC) in the Gulf of
Maine/Georges Bank region since autumn 1963 and spring 1968 (Azarovitz 1981). The NEFSC spring
and autumn bottom trawl survey data were analyzed to evaluate trends in total
and exploitable abundance and biomass of Acadian redfish, and trends in the age
composition of the population.
Trends in Total Abundance and Biomass
Abundance (stratified mean number
per tow) and biomass (stratified mean weight per tow) indices were calculated
from NEFSC spring and autumn surveys based on strata encompassing the Gulf of Maine and portions of the Great South
Channel (strata 24, 26–30, 36–40; Table 4 and Table 5; Figure 4 and Figure 5). Trends in total abundance and biomass are
similar in both spring and autumn surveys. Relative abundance of redfish has declined sharply in both survey
series, from peak levels over of 100 fish per tow in the late 1960s and early
1970s to generally between 10 and 30 fish per tow during the mid 1980s through mid
1990s. The decline in biomass has been
of the same order. Both series suggest a slight increase in abundance and biomass between
the mid 1980s and 1990s followed by a sharp increase in autumn 1996 and spring
1997, and relative stability at these higher levels during the past decade.
Trends in Exploitable Abundance and
Biomass
Indices of exploitable abundance and biomass were derived by applying a
series of mesh selection ogives to the time series of bottom trawl survey data. First, a catch-weighted average mesh size was
calculated for each year from 1964–1993. The average mesh size increased from 2.5–3 in (64–76 mm) during the
1960s to about 5.5 in (140 mm) during the late 1980s and early 1990s (Figure 6),
then to 6–6.5 in (152–165 mm) at present. Five periods were identified and data from early mesh selection studies (Clark 1963; Clay 1979; McKone 1979; Nikeshin et al. 1981) were used to
construct mesh selectivity curves based on estimates of alpha and beta derived
by fitting logistic curves to published data.
These selectivity factors (alpha and
beta) were applied to the NEFSC spring and autumn survey data to ‘filter out’
those fish that would not have been retained by the approximate mesh size in
use by the commercial fleets during each period. The same stratified mean calculations of
abundance and biomass were performed on the ‘filtered’ data as for the total abundance
and biomass indices.
During the 1960s, most of the
population of redfish was above the size that would be retained by the 2.5–3 in
(64–76 mm) mesh used by the commercial fleets. During the late 1990s and early 2000s, most of the population of redfish
was below the size that would be retained by the 5.5–6 in (140–152 mm) mesh
used by the commercial fleets. Thus,
recent increases in total abundance and biomass are not reflected in the
exploitable component of the stock under the present management regulations (Figure 7 and Figure 8). At
present the portion of the total biomass stock that is exploitable is very
small compared to the earlier periods (Table 6).
Age Composition Indices
Stratified mean indices of abundance
at age were calculated from NEFSC autumn survey data from 1975 through 2004 and
from NEFSC spring survey data from 1975 through 1990 with some exceptions. The survey otolith collection is routinely aged
to the maximum possible age. For this
analysis, all ages greater than 50 years were binned at 50+. As the autumn survey has provided the most
consistent set of abundance and biomass indices, priority was given to ageing
of the autumn survey otolith collection. Annual age compositions from all available spring and autumn surveys are
depicted in Figure 9, and the composite age distribution from the autumn survey
is illustrated in Figure 10. The age
composition data clearly illustrate recruitment patterns and changes in age
structure of the population. In 1975,
the population still appeared to exhibit a relatively broad age structure. The 1971 year class is prominently featured
in 1975, followed by the 1978 year class in the early 1980s; these two year
classes continued to dominate the demographics of the population through the
1980s.
More recently, the 1985 and 1992
year classes appear most prominent. Despite this improvement in recent recruitment, the age structure of the
population during the late 1990s and early 2000s remains severely truncated
compared to 1975 and earlier.
Accuracy and
Precision of Survey Ages
For
Acadian redfish, age-reader precision was estimated once from second readings
of random subsamples from the NEFSC 2004 autumn bottom trawl survey. The precision level was 89% agreement, with a
total CV of 1.0%, between first and second readings (Figure 11), indicating a
moderate level of consistency in age determinations for this long-lived
species.
ESTIMATION OF FISHING MORTALITY AND STOCK SIZE
Population dynamics model
In this section, an age-structured
assessment model is developed for redfish. Age-structured population dynamics of redfish were modeled in a standard
manner using forward-projection methods for statistical catch-at-age analyses (Fournier and Archibald
1982; Methot 1990; Ianelli and Fournier 1998; Restrepo and Legault 1998). The
age-structured model (RED) employed at the last peer review of this assessment
in 2001 (SAW 33) was updated with NEFSC spring and autumn bottom trawl survey
biomass indices and NEFSC autumn bottom trawl survey age compositions through
2004. The population dynamics model
is briefly described below and a full description
of the age-structured model is provided in Mayo et al. 2002.
The age-structured model is based on
forward projection of population numbers at age. This modeling approach is
based on the principle that population numbers through time are determined by
recruitment and total mortality at age through time. The population numbers at age matrix N=(Ny,a)YxA has dimensions Y by A, where Y is the number of years in the assessment time
horizon and A is the number of age classes modeled. The oldest age (A) comprises a plus-group
consisting of all fish age A and older. The
time horizon for redfish is 1934–2004 (Y=71). The number of age classes is 26, representing ages 1–26+. Input data to the
model includes the total landings (1934–2004), commercial CPUE index (1942–1989),
commercial landings at age (1969–1985), NEFSC spring and autumn total biomass
indices, and the autumn survey age composition (1975–2004).
Forward
Projection Model Results
Fishing
mortality on Acadian redfish has generally remained quite low compared to many
other species. Average fully recruited
fishing mortality (ages 9+) remained between 0.05 and 0.15 from the 1940s through
the 1960s even as landings also declined (Figure 12). Fishing mortality increased
substantially during the 1970s and early 1980s, peaking at 0.29 in 1979 and 1982. These results are very similar to those
obtained using VPA during the early 1980s (Mayo et al. 1983, NEFSC 1986). With
the subsequent disappearance of the directed fishery, fishing mortality
declined sharply, reaching extremely low levels during the 1990s and 2000s.
The spawning
stock biomass of redfish declined from over 500,000 mt in the early 1940s,
shortly after exploitation commenced, to 120,000–130,000 mt between 1957 and
1971 (Figure 13). Spawning biomass
declined further to very low levels of less than 30,000 mt during most of the
1980s and early 1990s before increasing to almost 180,000 mt in 2004. The estimate of
the 2000 spawning stock biomass based on the present assessment is within 5% of
the estimate obtained from the 2001 assessment.
Recruitment
at age 1 remained relatively constant for about two decades from the mid 1940s
through the mid 1960s, averaging about 60 million fish (Figure 13). Following this period of relative stability,
strong or moderate year classes appeared infrequently until the 1990s, when
moderate to strong year classes once again appeared on a more regular
basis. The largest year classes in the
almost 60-year series are the 1971 (246 million fish at age 1) and 1992 (281
million fish at age 1) cohorts. Survival
ratios (recruits per unit of spawning biomass) also illustrate the relatively
high survival of the dominant 1971 and 1992 year classes, as well as the
moderate 1978 and 1989 year classes (Figure 14).
Sensitivity
Analyses
The initial
version of the age-structured forward projection model (RED) was refined after
2001, and is now a component of the NOAA Fisheries Toolbox (NFT) stock
assessment software, STATCAM. This
version, while identical to RED in most approaches, provides for additional
weighting of input data, depending on the length of the time series. Comparative runs of both models were
conducted on data sets available at the previous peer review meeting (1934–2000)
and at the present meeting (1934–2004) to determine whether differences in
modeling approaches produced different estimates of spawning biomass and F. While both models produce very similar
estimates of spawning stock biomass and fishing mortality over time (Figure 15),
the STATCAM model (STATCAM 2005) is generating a higher rate of increase in SSB
during the past decade than the biomass produced by the original RED model. Both models produce the same status
determination for this stock, but because the results from the original RED
model were used to derive the biomass reference point, the update from this
model is used for current status determination.
BIOLOGICAL REFERENCE POINTS
Estimates of
recruitment obtained from the age-structured biomass dynamics model reviewed at
SAW 33 were used to infer the probable recruitment that could be produced by a
rebuilt stock as described in NEFSC (2002b). Recruitment estimates derived by the model from the1952–1999 year
classes served as the basis for evaluating trends and patterns in recruitment. The stock recruitment data suggest an
increase in the frequency of larger year classes (>50 million fish) at
higher biomass levels (Figure 16); therefore, recruitment estimates
corresponding to the upper quartile of the SSB range served as the basis for
deriving mean and median recruitment estimates. In accordance with the recommendation of the Stock Assessment Review
Committee (SARC) at SAW 33, the estimate of F50% (0.04)
is taken as a proxy for FMSY. This fishing mortality rate produces 4.1073 kg of spawning stock biomass
per recruit and 0.1429 kg of yield per recruit. The resulting mean recruitment of 57.63 million fish results in an SSBMSY estimate of
236,700 mt when multiplied by the SSB per recruit, and an MSY estimate of 8,235
mt when multiplied by the yield per recruit.
Reference points
derived from the non parametric approach are:
MSY = 8,235mt
SS BMSY = 236,700 mt
FMSY = F50% MSP = 0.04
CONCLUSIONS
It was determined
(NEFSC 2002b) that the stock could not be rebuilt to BMSY by 2009 even at
F=0.0. Therefore, the rebuilding
scenario invoked a 10 year plus 1 mean generation time (31 years for Acadian
redfish) to achieve rebuilding. This
results in an Frebuild = 0.013. Based on the results from the present assessment, spawning stock biomass
in 2004 is estimated at 175,800 mt, 74% of BMSY and F in 2004 is
estimated at 0.002, well below FMSY. Thus, the stock is not overfished and overfishing is not occurring.
ACKNOWLEDGMENTS
We are indebted to the 2005 Groundfish
Assessment Review Meeting (GARM II) participants who provided a thorough,
constructive review of this assessment.
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