|
Resource
Ecology &
|
Survey Estimates |
|||
Most
recent (year) |
Previous (year) |
%
change from previous estimate |
|
Alaska plaice | 546,522 (1999) |
452,600 (1998) |
+21% |
Miscellaneous flatfish |
69,730 (1999) |
73,900 (1998) |
-6% |
The assessment
methodology for the other flatfish SAFE chapter was
identical to last year’s with the exception of the
Alaska plaice assessment (within the other flatfish
chapter), in which the software program AD Model
Builder was used.
The table below contains the year 2000
projections of ABC and spawning biomass from the
1998 and 1999 stock assessments for BSAI Alaska
plaice. The yield projections were based upon
the F40% fishing mortality rate. The year 2000
projections for Alaska plaice increased relative
to the 1998 SAFE because the actual fishing
mortality in 1999 was less that the F40% rate.
Alaska Plaice Year 2000 Projection (t) |
|||
1998 SAFE | 1999 SAFE | %
change from 1998 |
|
ABC | 74,366 | 101,913 | +37% |
Spawner biomass |
132,990 | 186,880 | +40% |
Bering
Sea/Aleutian Islands Pacific Ocean Perch and Other
Red Rockfish
The methods used to assess Pacific ocean perch
(POP) were identical to last year. The
following table contains the most recent bottom
trawl survey biomass estimate in metric tons (t) for
the Pacific ocean perch and a comparison to
previous survey estimates.
Survey Estimates (t) |
|||
Most
recent (year) |
Previous (year) |
%
change from previous estimate |
|
Pacific
ocean perch (AI) |
713,841 (1997) |
423,045 (1994) |
+69% |
Pacific
ocean perch (EBS) |
53,266 (1991) |
75,685 (1988) |
-30% |
Current biomass
estimates for other red rockfish (northern rockfish,
rougheye rockfish, shortraker rockfish, and
sharpchin rockfish) were obtained by averaging the
estimated biomass in the recent U.S. domestic survey
(ranging from 1988 to 1997). In contrast with
previous years, earlier surveys were not considered
because of concerns with consistency with recent
surveys. This resulted in removing an
unusually high biomass estimate for the EBS northern
rockfish, and thus lowered the estimated biomass.
The year 2000 ABCs for AI Pacific ocean perch and
EBS Pacific ocean perch are shown below.
Year 2000 Projection (t) |
|||
1998 SAFE | 1999 SAFE | %
change from 1998 |
|
Pacific
ocean perch (AI) ABC Spawner biomass |
12,000 117,240 |
12,279 97,780 |
+2% -17% |
Pacific
ocean perch (EBS) ABC Spawner biomass |
2,000 25,300 |
2,599 24,904 |
+30% - 2% |
The recommended ABCs for other red rockfish were obtained from multiplying 0.75 times the product of the natural mortality rate and the average biomass from the U.S. domestic trawl surveys. A summary of the recommended 2000 ABC with the recommended 1999 ABC is shown below.
Recommended ABC |
|||
1998 SAFE |
1999 SAFE |
%
change from 1998 |
|
Northern/Sharpchin (EBS) | 537 | 34 | -94% |
Rougheye/Shortraker (EBS) | 236 | 160 | -32% |
Northern/Sharpchin (AI) | 4230 | 5153 | +22% |
Rougheye/Shortraker (AI) | 965 | 646 | -33% |
Bering
Sea/Aleutian Islands Other Rockfish
The methods used to assess other rockfish were
identical to last year. ABC was obtained by
multiplying 0.75 times the product of the natural
mortality rate and the average biomass from the U.S.
domestic trawl surveys. Because the most
recent survey was conducted in 1997, the estimated
mean biomass and recommended ABC were identical to
those in the 1998 SAFE. The estimated biomass
of other rockfish in the EBS and AI was 7,029 t and
13,041 t, respectively. The recommended ABC
for the EBS and AI was 369 t and 685 t,
respectively.
Bering Sea/AleutianIslands Atka Mackerel
Relative to the November 1998 SAFE report, the
following substantive changes have been made in the
current draft of the Atka mackerel chapter. The
1999 TAC was used as a proxy for the 1999 catch.
The most recent survey biomass estimate (1997)
was down about 50% relative to the 1994 survey
estimate.
No substantive changes were made in the assessment
model. A stochastic projection model was used
to project 2000 biomass and yield, and to evaluate
alternative harvest policies for stocks managed
under Tiers 1, 2, or 3 of Amendment 56.
The mean recruitment from the stochastic projections
was 622 million recruits, which gives an estimated
B40% level of 154,300 t. The projected age 3+
biomass at the beginning of 2000 was 565,150 t. The
projected female spawning biomass for 2000 was
162,500 t; representing a 0.9% decrease relative to
last year’s 2000 estimate. The projected
2000 yields at F40% and FABC were 102,700 and 78,500
t, respectively. The 2000 recommended ABC was
78,500 t corresponding to F = 0.26, that
represents a 7% increase relative to the 1999 ABC
and an 11% increase relative to last year’s
projected 2000 yield. These increases in the
face of a declining stock trend, were due to a
change in harvest strategy and the use of stochastic
rather than constant recruitment in the projections.
The projected 2000 OFL at F35% was 119,300 t.
Bering Sea/Aleutian Islands Squid and Other
Species
The “other species” management group has
been established to account for species which are
currently of slight economic value and upon which
there is little, if any, directed fishing. However,
these species could have economic value in the
future, and many are important components of the
ecosystem as prey for commercial fish species,
marine mammals and birds. Squid was considered
separately from the “other species” management
group, which includes sculpins, skates, sharks, and
octopus. Smelts were removed from the “other
species” group and moved to the forage fish group
beginning in 1999 as a result of fishery management
plan (FMP) amendments 36 and 39 to the Bering Sea
and Aleutian Islands and Gulf of Alaska groundfish
FMPs.
The recommended ABC for squid in the year 2000 was
calculated as 0.75 times the average catch from
1978-95, or 1,970 t; this was unchanged from 1999.
The recommended OFL for squid in the year 2000
was calculated as the average catch from 1978 to
1995, or 2,624 t; this was also unchanged from 1999.
The recommended ABC for the other species complex in
the year 2000 was calculated as the average catch
from 1977 to 1998, or 26,800 t. This was
unchanged from 1999. The recommended OFL for
the other species complex in the year 2000 was
122,100 t, which was calculated by multiplying an
estimate of the natural mortality rate (M=0.2) by a
biomass estimate for the complex (average of
the last three EBS bottom trawl surveys plus the
most recent Aleutian Islands bottom trawl survey =
610,400 t). The OFL and biomass estimate for
other species for the year 2000 were 5% lower than
those calculated for 1999.
Gulf of Alaska Walleye Pollock
There were several changes made in the input
data to the stock assessment model used this year.
Biomass estimates and length composition from
the 1999 triennial bottom trawl survey were
included. The 1999 triennial survey estimate
of pollock biomass west of long. 140EW was 606,295
t, a 9% decline from 1996. Several factors
complicate interpretation of the 1999 biomass
estimate. First, bottom temperatures in 1999
were generally cooler than during other triennial
surveys. The vulnerability of pollock to the
bottom trawl survey may be temperature-related,
either due to changes in vertical distribution or
due to inshore-offshore changes in spatial
distribution. Second, estimates of total
biomass and biomass distribution between statistical
areas were strongly affected by a few large tows.
The coefficient of variation of the gulf-wide
biomass estimate was 0.38, more than double any
previous triennial survey. The largest
concentration of pollock biomass was estimated to be
in the Shumigan area (72%), followed by the Kodiak
(18%), Chirikof (9%) and West Yakutat INPFC areas
(1%). Furthermore, additional age data were
used in the 1999 assessment. Pollock age
composition from the 1997 and 1998 Shelikof Strait
EIT surveys were included. Age composition and
catch from the 1998 fishery were included. Biomass
and length composition data from the ADF&G
coastal bottom trawl survey for 1989-98 were
evaluated for consistency with other information,
and were included in the base-run model.
Gulf of Alaska pollock were assessed using an
age-structured population model developed using
ADModel Builder (a C++ software language
extension and automatic differentiation library).
The stock assessment was extended eastward to 140EW
longitude to coincide with the area open for
trawling in the Gulf of Alaska (Statistical Areas
610-640). The annual catch and triennial
bottom trawl biomass estimates were revised to
correspond to this area. This change addresses
the NPFMCs Scientific and Statistical Committee’s
comments about the discrepancy between assessment
and management areas in the eastern Gulf of Alaska.
A separate ABC for pollock in the no-trawl zone in
southeast Alaska (East Yakutat and Southeastern
INPFC areas) was obtained under Tier 5 of NPFMC
harvest policy.
To address Plan Team and SSC concerns about
unsurveyed pollock in Prince William Sound (PWS),
the biomass from the triennial survey and the
ADF&G survey in PWS in 1999 were added to obtain
a total biomass estimate. NMFS vessels
surveyed the northern gulf within 2 weeks of the
ADF&G survey in PWS. The adjustment factor
for the 1999 surveys (PWS + Triennial)/Triennial was
applied to earlier triennial surveys and increased
the biomass time series by 1.05%.
There were several changes in assessment results
this year. Spawning biomass in 2000 was projected to
be 214,900 t, which was 35% of the unfished biomass
of 619,000 t, thereby placing Gulf pollock in
sub-tier “b” of Tier 3 NPFMC harvest guidelines.
Age 3+ biomass for the region west of 140EW in
2000 was projected to be 588,000 t for the base-run
model and 651,000 t for a model without the
ADF&G survey data. These estimates were
similar to biomass projections made last year, which
ranged from 581,500 t to 674,500 t. The
recommended 2000 ABC for the GOA stock was 111,306
t, representing an increase of 28% from the
projected 2000 ABC in the 1998 assessment for the
central and western GOA (80,139 t). This
projection was based on an adjusted F40% rate.
The higher projected 2000 ABC was caused by
several factors: a larger assessment
area including PWS and all of West Yakutat;
increased abundance of the 1995 year class based on
1998 fishery age composition data (492 million as
compared to 181 million in the 1998 assessment); and
the use of average fishery selectivity for 1992-99
both to calculate SPR rates and to project harvests.
Last year’s assessment used the 1985-98
average selectivity to calculate SPR rates, and
1994-98 average selectivity to project yields and
the correction of an error in the calculation
of SPR rates. The estimated 2000 OFL for the
GOA stock was 130,758 t. For pollock in
Southeast Alaska (East Yakutat and Southeastern
INPFC areas), the ABC recommendation was 6,460 t.,
an increase of 2% for a comparable area in the 1998
assessment). Various approaches to
apportioning the ABC using triennial survey biomass
were evaluated. A regional allocation based on
a four survey average was recommended (41.0%
Shumigan, 24.4% Chirikof, 32.1% Kodiak, 2.5% West
Yakutat INPFC areas). Since the assessment now
explicitly includes the pollock biomass in Prince
William Sound, the harvest guideline for PWS pollock
should be subtracted from the total ABC prior to
regional allocation.
Gulf of Alaska Pacific Cod
Relative to the November edition of last
year’s GOA SAFE report, the following substantive
changes have been made in the Pacific cod stock
assessment.
Several new sources of data were used in the 1999
GOA cod assessment. Size composition data from
the 1998 and January-August 1999 commercial
fisheries were incorporated into the model. Size
composition data from the 1999 GOA bottom trawl
survey were incorporated. The biomass estimate
from the 1999 GOA bottom trawl survey was
incorporated (the 1999 estimate of 305,823 t was
down about 43% from the 1996 estimate). Weight-at-length
data from recent GOA bottom trawl surveys were
incorporated.
There were no changes in the assessment model this
year. The estimated 2000 spawning biomass for the
GOA stock was 111,000 t, down about 15% from last
year’s estimate for 1999 and down about 3% from
last year’s FABC projection for 2000. The
estimated 2000 total age 3+ biomass for the GOA
stock was 567,000 t, down about 13% from last
year’s estimate for 1999 and up about 7% from last
year’s FABC projection for 2000. The recommended
2000 ABC for the GOA stock was 76,400 t, down about
16% from last year’s recommendation for 1999 and
down about 10% from last year’s FABC projection
for 2000. The estimated 2000 OFL for the GOA
stock was 102,000 t, down about 24% from last
year’s estimate for 1999 and down about 11% from
last year’s FOFL projection for 2000.
Gulf of Alaska Arrowtooth Flounder
Catch for 1998 was updated, and an age-based
model run using different natural mortality values
for males and females with added survey age
composition data from 1984, 1987, and 1990. The
1999 NMFS survey biomass estimate and length
composition were added to the model. The
natural mortality for males was set higher than for
females to obtain a sex ratio of about 70% female in
the population. Length composition data were
fit using a fixed length-age transition matrix.
The 1998 assessment used the length-based
synthesis model, estimating growth parameters in the
model. In the 1998 assessment the natural
mortality estimates and the selectivities by length
were the same for males and females.
Survey biomass estimates from halibut trawl surveys
in the 1960s, groundfish trawl surveys in the 1970s
and NMFS triennial trawl surveys from 1984 to 1999
were used. Selectivities were estimated by a
smooth function that was constrained to be
monotonically increasing with age for the fishery
and survey. The estimated biomass from the
model increased from about 206,600 t in 1961 to 1.69
million t in 1994, then declined to about 1.592
million t in 1999. In the 1998 assessment the
survey selectivities by age for males was lower than
females resulting in a higher population biomass
than in the current assessment (about 2,126,000 t in
1999). In the current model the survey
selectivities by age for males and females are more
similar, resulting in population biomass estimates
that are closer to the survey biomass estimates.
The 2000 yield using F40% was 145,361 t. OFL
using F35% was 173,915 t. The 1999 ABC using
F40% was 217,106 t.
Gulf Of Alaska Flatfish
Catch has been updated through 9 October 1999.
ABCs were estimated using the 1999 survey
biomass estimates for all species except Greenland
turbot and deep-sea sole where the mean catch from
1978 to 1995 was used.
Catches for species in the deep-water or
shallow-water groups were estimated from 1978 to
1998 by multiplying the group catch estimate by the
estimate of the fraction of each species in the
catch based on observer data.
The 1999 triennial trawl survey biomass was used as
current biomass for calculation of ABC. Rock
sole ABC was estimated using F40% calculated using
the Bering Sea rock sole maturity schedule. Greenland
turbot and deep-sea sole ABC and OFL were calculated
using average catch. ABCs for other flatfish
except rock sole were estimated using F = 0.75 M.
The ABC for Dover sole was estimated using the
1999 survey biomass which should be more applicable
than the 1996 survey, since it covered the depth
range of Dover sole (to 1,000 m). The 1990 to
1996 surveys included depths to 500 m only, which
did not survey the population depth range of Dover
sole.
Gulf of Alaska Atka Mackerel
There were very few changes made to the current
year’s Atka mackerel assessment. Catch data
were updated and research catches were included.
There were no changes in the assessment
methodology and no changes in assessment
results.
In this assessment several issues were highlighted.
There was no reliable estimate of current
biomass from the Gulf of Alaska bottom trawl survey.
Using Tier 6 criteria, OFL was set equal to
the average catch from 1978 to 1995, which equals
6,200 t. It was recommended that the ABC for
Atka mackerel in the GOA be 600 t, enough to satisfy
only the anticipated bycatch needs of other trawl
fisheries, principally those for Pacific cod,
rockfish, and pollock. This recommendation was
based on the following reasons: a) there was
no reliable estimate of current biomass, b) Leslie
estimates of local population sizes suggest that
abundance has declined significantly in localized
areas from 1992-94, and c) the species has exhibited
vulnerability to fishing pressure in the past.
Gulf of Alaska Thornyheads
This year we updated the model introduced in
1997 with available recent data, including 1998
harvest levels by gear, and biomass estimates from
the 1999 NMFS triennial trawl survey. Alternate
models examined assumptions regarding recruitment
variability and survey catchability. Results
from this year’s analyses were similar to last
year’s, although harvest levels have increased
slightly for next year under the F40% fishing
mortality.
The following table summarizes the ABC
recommendations and status of spawning biomass level
for the past few years relative to the current
assessment.
Assessment Year |
Projection Year |
Female Spawning Biomass |
ABC Recommendation |
1996 | 1997 | 20,331 t | 1,700t |
1997 | 1997 | 22,812 t | - |
1997 | 1998 | 22,778 t | 2,000 t |
1998 | 1997 | 23,473 t | |
1998 | 1998 | 23,483 t | |
1998 | 1999 | 23,100 t | 1,990 t |
1999 | 1997 | 22,809 t | - |
1999 | 1998 | 22,932 t | - |
1999 | 1999 | 23,095 t | - |
1999 | 2000 | 23,084 t | 2,359 t |
Gulf of Alaska
Other Species
The first assessment of Gulf of Alaska other
species was introduced in 1999. This
assessment considered fishing impacts on sharks,
skates, sculpins, smelts, octopi, and squids in
1990-98 (smelts were removed in 1999). In the
past, TAC for this category has been set at 5% of
the sum of all GOA target species TACs. The
proposed assessment model was a simple state-space
model incorporating both observation error and
process error in biomass and exploitation rate
estimates. Input data included catch estimates
by species group from 1990-98, and 1984-99 GOA
triennial trawl survey biomass estimates for each
species group. Assessment scientists also
examined catch and biomass estimates for grenadiers,
which are not included in the other species
category.
Catches of fish and invertebrates of the other
species category were very small compared to those
of target species in the Gulf of Alaska. It
appears unlikely that the observed 1990-98 bycatch
of other species has had a negative effect on
biomass at the species group level, according to the
available trawl
survey data. Grenadiers, while not
included in the other species category, may be the
dominant fish in deeper habitats and were caught in
sufficient numbers to warrant additional attention,
especially because they may be very long- lived
species. Data limitations were severe for all
species groups in this category, and further
investigation is necessary to ensure that all
components of the other species complex are not
adversely affected by groundfish fisheries. Furthermore,
if target fisheries develop for any component of the
other species group, effective management will be
extremely difficult with the current limited
information.
Although changing the procedure for establishing the
TAC of other species requires an amendment to the
GOA FMP, we propose separate ABC
and OFL levels for each species group within
other species to ensure that less productive groups
are not over harvested. These individual ABCs
sum to slightly less than the recent aggregate TACs
in the range of 14,000 t, but observed catches in
each of the categories have never exceeded these
proposed ABCs in the domestic fishery, with the
exception of octopus catches in 1992 and 1997.
We believe that cephalopod biomass was
substantially underestimated by the bottom trawl
survey, resulting in overly conservative estimates
of ABC and OFL for these species groups; but we have
no other data on which to base recommendations.
Understanding other species population dynamics is
fundamental to describing ecosystem structure and
function in the Gulf of Alaska, because each group
in other species plays an important ecological role.
The species groups in this category occupy all
marine habitats from pelagic to benthic, near shore
to open ocean, and shallow to slope waters. Regardless
of management decisions regarding TAC and the future
structure for other species, it is essential that we
continue to improve species identification, survey
sampling, and biological data collection for the
species in this category if we hope to ensure their
continued conservation.
By Anne Hollowed.
RESOURCE ECOLOGY AND ECOSYSTEM MODELING
PROGRAM
Stomachs collected totaled 1,010 for the West
Coast. Laboratory analysis was performed on
1,423 groundfish stomachs from the eastern Bering
Sea, 522 from the Aleutian Islands region, and 160
from Gulf of Alaska. Nine observers returned
with stomach samples (602 walleye pollock) collected
from the eastern Bering Sea.
Diets of Pacific and Giant Grenadier
In a collaborative investigation with Jeff
Drazen (Scripps Institution of Oceanography) and
Jerry Hoff (RACE Division), the feeding habits of
Pacific grenadier (Coryphaenoides acrolepis)
and giant grenadier (Albatrossia pectoralis)
from the continental slope off Washington, Oregon,
and California were analyzed. A total of
497 Pacific grenadier and 617 giant grenadier
were used in this analysis. We found an
ontogenetic shift in the diet of Pacific grenadier
from benthic epifauna and infauna (amphipods,
cumaceans, and polychaetes) to nekton and scavenged
material (Gnathophausia spp., squid and fish).
We found a decrease in squid and an increase
in midwater fishes and scavenged material in the
diet with increasing size of the giant grenadier
examined. These shifts were attributed
primarily to increasing mouth size and locomotory
ability. Significant differences were found
between the diets of Pacific and giant grenadier
where they co-occur, indicating some degree of niche
separation between the two species.
By Troy Buckley.
Winter Feeding Habits of Pacific
Whiting (Merluccius productus)
In January 1997, 226 stomach samples from
Pacific whiting were collected during a spawning
survey off southern California. Tows were made
in midwater at depths of 165 to 400 m over bottom
depths of 750 to 1800 m. The gonads of Pacific
hake were categorized by their stage of development
based on gross characteristics of the whole organ.
In this study, 80% of the stomachs were empty
and 20% contained prey items. In stomachs that
contained food, fishes dominated the weight
composition (88%) and numerical composition (52%) of
the diet and had a high frequency of occurrence
(60%). All of the fish were myctophids
(lanternfishes) except for one incidence of
cannibalism. Myctophids have been found in
other studies, but not as the dominant prey. The
high percentage of empty stomachs was found in all
reproductive stages including immature Pacific hake.
We believe our results reflect a lack of other
prey in the study area due to seasonal,
geographical, and interannual influences.
By Geana Tyler.
PICES Science: 1999
The PICES (North Pacific Science Organization)
Eighth Annual Meeting was held 8-17 October 1999 in
Vladivostok, Russia. One hundred and fifty-one oral
presentations and 99 posters were given at the
meeting. More than 300 scientists attended the
event.
The year 1999 was important for PICES because of
several ‘firsts’ in the area of international
collaborative field and laboratory work by the PICES
scientific community. In 1999 a practical
workshop was held in Vancouver Harbor by scientists
of the Marine Environmental Quality Committee’s
Working Group 8 on Practical Assessment Methodology.
This was the first time scientists from all
PICES-member countries participated in a mutual
field and laboratory effort. The
workshop set the stage for future collaborative work
in the study of marine environmental quality. Similarly,
the Physical Oceanography and Climate Committee’s
Working Group 13 on Carbon Dioxide in the North
Pacific also held a multinational technical workshop
in 1999. Their intercalibration exercise for
laboratory measurements of carbon dioxide will
ensure the high quality of North Pacific carbon
dioxide measurements in the future, allow
multinational synthesis of carbon dioxide studies,
and lead to improved understanding of carbon cycle
processes. Finally, the PICES-GLOBEC CCCC
Program successfully obtained funding from the North
Pacific Marine Research Program to perform a 2-year
study to initiate continuous plankton recorder (CPR)
monitoring in the north. The next challenge
will be to find a way to maintain this monitoring as
a long-term PICES effort.
Many PICES scientific efforts were completed in 1999
through publication in either the PICES
Scientific Report Series, in special journal
volumes, or as books. The proceedings of the
1997 Science Board Symposium on “Ecosystem
dynamics in the eastern and western gyres of the
subarctic Pacific” was published in volume 43(2-4)
of Progress in Oceanography. The final endpoint of
the Science Board’s Working Group 5 on the Bering
Sea came with the publication of the book
“Dynamics of the Bering Sea” by University of
Alaska Sea Grant. Three volumes of the PICES
Scientific Report series were produced in 1999:
Volume 10 has the proceedings of the 1998
Science Board Symposium on El Niño 1997-98 events;
Volume 11 has the proceedings of the 1998 PICES
GLOBEC CCCC Program MODEL, REX, and MONITOR
workshops; and Volume 12 has the proceedings of the
second PICES workshop on the Okhotsk Sea and
adjacent areas.
Several working groups completed their work in 1999
and are preparing to publish results in 2000. The
Physical Oceanography and Climate Committee’s
Working Group 10 on Circulation and Ventilation in
the Japan/East Sea will place their report on the
PICES web site as a revisable, living document.
The Fishery Science Committee’s Working
Group 12 on Crabs and Shrimp and Biological
Oceanography Committee’s Working Group 11 on
Consumption of Marine Resources by Marine Mammals
and Seabirds will also be working toward publication
of their final results in the year 2000.
The PICES-GLOBEC CCCC Program continues its work on
integrating and stimulating national GLOBEC research
efforts in the North Pacific. The Regional
Experiments (REX) Task Team is presently focusing on
comparative work on herring in the North Pacific.
They completed an interesting workshop on
“Herring and Euphausiids” and are planning a
workshop for 2000 on herring population trends and
trophodynamics. The Basin Scale Studies (BASS)
Task Team has an Iron Fertilization Panel that is
planning international field experiments in the
subarctic North Pacific to understand the role of
iron in influencing production. The MODEL Task
Team is undertaking two workshops in 2000, one to
build lower trophic level models in several areas of
the North Pacific and the second one to link these
models to upper trophic level models. The
MONITOR Task Team completed a successful workshop on
the Global Ocean Observing System (GOOS) and to
examine the future role of PICES in this growing
international program. As an outcome of the
workshop, PICES will be developing an action plan
that will outline how PICES will be taking an active
and leading role in the implementation of GOOS at a
North Pacific level.
New collaborations and working groups will begin in
the year 2000. An advisory panel on CPR
surveys in the North Pacific was formed, which will
advise the CCCC-MONITOR Task Team on the design of
its CPR experiments and work. Marine mammal
and bird experts now have their own Advisory Panel
under the Biological Oceanography Committee (BIO).
They will be providing scientific advice to
BIO and CCCC, and providing leadership to marine
mammal and bird researchers in the North Pacific in
ecosystem research. The Marine Environmental
Quality Committee has just formed a Working Group to
examine the ecology of harmful algal blooms in the
North Pacific, and the Fisheries Science Committee
has formed a Working Group to consider the
implications of climate change to fisheries
management.
PICES IX will be held 20-28 October 2000 in
Hakodate, Japan.
By Pat Livingston.
Production figures for the 1 January to 31 December 1999 were:
flathead sole |
99 |
|
rock sole |
50 |
|
rex sole |
236 |
|
Alaska plaice |
419 |
|
northern rock sole |
1,004 |
|
yellowfin sole |
1,257 |
|
arrowtooth flounder |
870 |
|
walleye pollock |
12,941 |
|
sablefish |
1,194 |
|
Atka mackerel |
245 |
|
Pacific whiting |
4,951 |
|
Pacific ocean perch |
2,607 |
|
northern rockfish |
1,137 |
Total production figures were 27,010 with 8,450 test ages and 206 examined and determined to be unageable.
At the request of the Stock Assessment Program, the Observer Program has changed the sampling of fisheries to small random samples collected by all at-sea observers. This will affect the Age and Growth Program in two ways. First, during the second half of 1999 and into 2000 extra handling of otoliths requiring re-labeling and re-storing of vials will be required. Also, the number of species and numbers requested for ageing may change as a result of the random sampling method.
Joint research
between REFM and NMML using radionuclides to age
gray whales and bowhead whales was presented via a
poster at the 13th Biennial Conference on the
Biology of Marine Mammals in Wailea, Hawaii, held 28
November - 3 December 1999. The title of the
poster was “The Potential use of Pb-210/Ra-226
Disequilibria for Age Determination of Mysticete
Whales,” By Craig Kastelle, Kim Shelden, and
Daniel Kimura.
By Dan Kimura.
U.S. GROUNDFISH OBSERVER PROGRAM
During the fourth quarter of 1999, 127 observers
were trained, briefed, and equipped for deployment
to fishing and processing vessels and shore-side
plants in the Gulf of Alaska, Bering Sea, and
Aleutian Islands region. They sampled aboard
219 fishing and processing vessels and at 14
shore-side processing plants. These observers
were trained or briefed in various locations. The
Observer Program in Seattle trained 17 first-time
observers and briefed another 18 observers with
prior experience. The University of Alaska Anchorage
(UAA) Observer Training Center briefed 30 observers
and trained another 34. At the Observer Program’s
field offices in Dutch Harbor and Kodiak, 4
observers were briefed and 24 were excused from
briefing because they had just completed a cruise
successfully and were returning immediately to the
field. The fourth quarter 1999 observer
workforce comprised 40% new observers and 60%
experienced observers.
The Observer Program conducted a total of 212
debriefings during the fourth quarter of 1999.
Nine debriefings were held in Kodiak, 13 in
Dutch Harbor, 25 in Anchorage, and 165 in Seattle.
Highlights of 1999: CDQ and AFA
Fisheries
Implementation of the expanded Community
Development Quota (CDQ) program and of provisions of
the recently enacted American Fisheries Act (AFA)
continued during 1999. The CDQ program was
developed for the purpose of allocating fishery
resources to eligible western Alaska communities to
provide the means for starting or supporting
commercial fishery activities that would result in
ongoing, regionally-based, commercial fishery, or
related businesses. The CDQ program was initiated in
1992 with pollock and expanded to include fixed-gear
halibut and sablefish in 1995. In 1998, it was
further expanded to include multiple species of
groundfish and crab (MSCDQ). In 1999, NMFS was
responsible for monitoring the groundfish (including
pollock and sablefish) and halibut CDQs, and the
state of Alaska was responsible for monitoring the
crab CDQs.
The AFA, enacted by Congress in late 1998, made
changes to the pollock fishery in the Bering Sea and
Aleutian Islands region. These changes
reallocated fish among industry segments, provided
for the formation of fishing cooperatives, and
increased observer coverage levels on some
components of the fleet. The offshore
component of the fleet organized a fishing
cooperative in 1999 and has received increased,
mandatory observer coverage. More recently,
the Observer Program has been involved in
implementing aspects of the AFA related to
shore-side pollock. The shore-side component
is more complex than offshore and may involve NMFS
regulatory actions and a changing role for the
observer.
The MSCDQ and AFA catch accounting for offshore
processors is based entirely on data collected by
observers and, unlike the open access fisheries,
where observer data is used to manage a fleet-wide
quota, industry participants in the MSCDQ and AFA
fisheries require individual accounting of fish
harvested in each haul or set. This change in
expectations placed on observers, their data, and
the Observer Program in general has required much
Observer Program staff effort in developing special
selection criteria and training requirements for
observers, developing new sampling strategies and
regulations to enhance the observer’s working
environment, and changes to the data collection and
data management software systems.
Observer Program Review
An extensive, independent review of the Observer
Program is being carried out by Marine Resources
Assessment Group (MRAG) Americas, Inc. MRAG is
an independent consulting firm which provides
professional advice and services for the management
of marine fisheries throughout the world. The
purpose of the review is to provide recommendations
for changes in Program operations and organization
which might improve the Program’s ability to meet
its mission and goals. Their final report is
due later in 2000.
By Bob Maier.
SOCIOECONOMIC ASSESSMENTS PROGRAM
During the past
quarter, Center economists have been involved
principally in activities in support of the Pacific
and North Pacific Fishery Management Councils and
other cooperative efforts within the agency and
beyond. Five research activities are reported
on below.
Cost, Earnings, and Employment Survey
Final approval for the cost, earnings, and
employment survey of the Alaska BSAI pollock
industry was secured from the Office of Management
and Budget (see “Economics and Management of the
Alaskan Groundfish Fishery: a New Data Collection
Project,” AFSC Quarterly Report, April-May-June
1999.) Before questionnaires are sent out, a
letter will be sent to all potential respondents
indicating that they will receive a questionnaire in
approximately one week. Two weeks after the
questionnaires are mailed, a follow-up letter will
be sent to nonrespondents. A second follow-up
letter will be sent two week later to individuals
who have still not responded. There will also
be follow-up phone calls or e-mails in some cases.
Initial letters will be sent out 4 January and
questionnaires on 10 January.
Spatial Modeling of Groundfish
Fisheries
The Socioeconomic Assessment Program assisted with
the bioeconomic model of the New England Groundfish
Fisheries. A price model for groundfish developed at
the Northeast Fisheries Science Center was
integrated into the simulations to allow fish prices
to vary with supply. Simulations were then rerun.
The major conclusion from this work was that the
integration of downward sloping demand curves had
negligible impacts on the evaluation of the benefits
derived from alternative area closures. While
area closure tend to reduce output and increase
price in the short-run, they have the opposite
effect in the long-run, and the price effects
largely cancel out when considering the present
value of future revenues derived from the fishery
with and without area closures. The primary
conclusions from the research remain unchanged: 1)
by redirecting fishing effort to less productive
fishing areas, area closure can reduce effective
fishing effort substantially; 2) area closures
appear to offer a means of increasing revenues only
when effort levels are excessive, but greater gains
can usually be made by reducing nominal fishing
effort or through direct controls on total catch
levels; 3) area closures can provide habitat
protection and allow for increases in equilibrium
spawning stock biomass at a relatively low cost in
forgone revenues even when effort is already close
to MSY levels; 4) the location and shape of area
closures will have important effects not only on how
they affect overall harvest and revenue streams, but
which user groups and individuals benefit. These
effects are often not intuitively obvious, since
they often result indirectly from redistribution of
fishing effort.
Common Property Institutions
The Socioeconomic Assessment Program in
collaboration with the NMFS Alaska Regional Office
is initiating a study of common property
institutions that have been developed by managers
and by user groups in the BSAI groundfish fisheries
to describe the process by which the groundfish
resources off Alaska have been gradually transformed
from essentially open-access to more manageable
common property resources. In particular, the
study focuses on the de facto partitioning of the
larger groundfish fishery into a number of smaller
fisheries as delineated by vessel size, gear, mode
of operation, etc. and discusses how this may have
facilitated the development by user groups of
cooperative solutions to problems such as rent
dissipation and excessive bycatch. Selected common
property institutions that have been created in
these fisheries are described in terms of the
problems they were designed to solve, their success
or lack of success in doing so, and the factors that
influenced both emergence and success of these
institutions. The institutions examined in the
study include the North Pacific Fishery Management
Council, the Community Development Quota system, the
offshore Bering Sea pollock cooperative, and the
cooperative bycatch control system known as
Sea-State used by the non-pollock factory trawler
fleet.
Fishery Participation Rate Modeling
Members of the Socioeconomic Assessment Program
conducted econometric analysis for and coauthored
the working paper “Modeling the Effect of Fishery
Attributes on Participation Rates: The Kenai
Peninsula Marine Sport Fishery.” The paper
was prepared for use by NPFMC staff for use in an
analysis of potential regulations affecting the
Alaskan recreational halibut fishery.
Knowledge about factors that influence recreational
anglers’ participation decisions is important to
fishery managers. Changes in fishery
regulations, environmental quality, and resource
abundance, as well as trip cost, can affect the
expected net benefit associated with a fishing trip,
and therefore participation decisions. Models
of participation decisions are consequently directly
linked to natural resource damage assessment, the
measurement of recreational benefits, and economic
impact analysis. This study shows how hybrid
stated preference questions can be used to estimate
the affects of fishery attributes on participation
rates. The stated preference method is a
natural choice for such circumstances because
anglers’ participation decisions will likely
depend on multiple trip attributes. This
approach allows for the simulation of a wide variety
of alternative policy scenarios, many of which would
not be possible using data from observed fishing
activity. The non-linear model specification
allows for substitution and complementary effects
across attributes and the possibility of non-linear
marginal utility.
Excess Processing Capacity
Program members also assisted in estimating the
amount of excess capacity that exists in the
in-shore pollock processing sector. The
estimates were then used in an analysis of the
American Fisheries Act (AFA) conducted by economists
at the University of Washington.
Part of the analysis preformed at the Center was
based on how AFA has affected the rate of pollock
production in the at-sea sector between the years
1998 and 1999. This was an effort to determine
whether and to what degree AFA co-ops have led to a
reduction in the processing rate. The analysis
was based on 17 separate catcher/processors vessels
that processed Alaska pollock in both 1998 and 1999
(the year before and after the AFA took affect).
Based on this analysis, the 1999 harvest and
production rate was between 65 and 75 % of the 1998
rate. These results were then used to formulate a
similar type of prediction for the in-shore sector.
It was estimated that the BSAI in-shore pollock
processors would use less than 50 percent of their
processing capacity in 2000. Therefore, they
could increase their production by more than 100 %
without increasing their capacity.
By Joe Terry.