PICES XV
W2-3260
Oral
The Management Strategy Evaluation approach and the Gulf of Alaska walleye pollock
fishery
Z.T. A’mar, A.E. Punt and M.W. Dorn
University of Washington, Box 355020, Seattle, WA, 98195-5020, U.S.A. E-mail: zta@u.washington.edu
Management strategy evaluation (MSE) is the process of using simulation testing to examine the robustness of
proposed management strategies to error and uncertainty. MSE involves using a model (the “operating model”)
to represent the true underlying dynamics of the resource and to generate future data, an estimation model to
assess the state of the stock relative to agreed target and limit reference points at each time step based on the
simulated data, and a catch control rule to determine management actions (e.g., the Total Allowable Catch,
TAC) given the results of the stock assessment. The latter two steps constitute the management strategy. The
parameters of the management strategy can be selected to achieve desired (but conflicting) management goals
and objectives. The results of an MSE are performance measures that quantify the effectiveness of the
estimating model and the management strategy. An MSE is performed based on the Gulf of Alaska walleye
pollock fishery.
PICES XV
W2-3197
Oral
The impact of future climate trends on the key species and their fisheries off the Pacific
coast of Canada
Richard J. Beamish
Pacific Biological Station, Fisheries and Oceans Canada, 3190 Hammond Bay Road, Nanaimo, BC, V9R 5K6, Canada
E-mail: beamishr@pac.dfo-mpo.gc.ca
In Working Group 16, Canada identified approximately 11 species that were key to the economy of the Pacific
Coast fishery. There were five species of Pacific salmon, sablefish, Pacific herring, Pacific hake, Pacific
halibut, Pacific Ocean perch and Pacific cod. Dungeness crab and spot prawns are two more important
commercial species that could be affected by future trends in climate. The management of hatchery produced
salmon as well as the commercial production of farmed salmon are also key activities that are associated with
west coast sea food production. Production data for these species and activities will be presented at the
workshop. The impact of climate and climate trends on production will be reviewed through the use of simple
models and informed speculation. After discussions with representatives from other countries, a representative
number of these species and activities will be selected to be used in basin-scale comparative studies of past and
future climate impacts on production.
PICES XV
W2-2878
Oral
Linking multi-species fisheries to climate variability: A phenomenological approach
Andrea Belgrano
Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington, Seattle, WA, 98185, U.S.A.
E-mail: belgrano@u.washington.edu
Emergent empirical patterns in complex systems, such as those involved in multi-species fisheries, can be
generated by processes related to invariant-variant factors such as class-size, body mass, species abundance,
composition and interactions across different spatial and temporal scales. Such empirical patterns can be used to
account for ecosystem dynamics, structure and species associations or interactions over broad biogeographical
areas. Different climatological conditions can affect such interactions to result in patterns that show consistency
in relation to environmental conditions. A phenomenological framework linking climate variability to interannual dynamics in species production for the Eastern Bering Sea (EBS) will be presented.
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PICES XV
W2-3231
Oral
An overview of evidence for climate impacts on Northeast Pacific marine fishes and
recommendations for a framework for forecasting annual marine production
Anne B. Hollowed1 and Jennifer Boldt2
1
2
Alaska Fisheries Science Center, NOAA Fisheries, Seattle, WA, 98115, U.S.A. E-mail: Anne.Hollowed@noaa.gov
Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington, Seattle, WA, 98195, U.S.A.
A metric of scientific understanding is the ability to predict future outcomes based on knowledge of key
environmental forcing factors. Numerous publications provide evidence for climate impacts on marine fish.
This paper attempts to standardize this information by identifying a common suite of local, regional and basin
level ecosystem indicators for use in a comparative study. Production time series (e.g., growth and recruitment)
are compared to the ecosystem indicators in a systematic manner to identify the statistical significance of
hypothesized functional relationships. Numerical modeling, non-linear and linear techniques are used to
evaluate the relationships. Multivariate statistical analyses are used to identify commonalities between species
and regions. A common suite of years are held back from the analysis and used to evaluate the predictive power
of statistical relationships. Data sets are evaluated for evidence of responses to large scale climate shifts as well
as long term climate change. The analysis provides a framework for a PICES annual forecast of marine
production.
PICES XV
W2-3192
Oral
Fluctuations of fish populations in the waters off Korea and its adjacent regions
Yeong Gong1, Hee-Dong Jeong2, Jong-Hwa Park2, Ki-Tack Seong2, Sang-Woo Kim2 and In-Seong Han2
1
2
Korea Fisheries Associations, Seoul, 120-012, Republic of Korea. E-mail: hdjeong@nfrdi.re.kr
National Fisheries Research and Development Institute, 408-1, Shirang-Ri, Gijang-gun, Busan, 619-705, Republic of Korea
Long-term fluctuations of pelagic fish and squid populations in the Tsushima Warm Current (TWC) and
Kuroshio-Oyashio Current (KOC) regions are examined based on the catch records updated for the period of
1900-2003. Over the past 100 years the abundance of herring, sardine, anchovy, chub mackerel, saury and
common squid show synchronous patterns of variability in the two regions, which suggest that they are
influenced by common climate shifts. An orderly alternation of dominant (exhibiting a peak in abundance)
species has been observed in the two regions.
The different fishing activities and limited fishing grounds in the TWC region were responsible for the different
amplitude in the abundance trends between the two regions during the peak of cool-sardine period (1980s). The
phase difference of biological response of some species between the two regions to the climate shifts was
attributed to the heavy fishing and to the shifting of early stages of the species by the currents in the ecosystems.
Each of the species returning to the common source area (spawning grounds) after feeding in the two different
current systems could be exploited as a shared population and conserved as a single large population during the
abundant period.
PICES XV
W2-3234
Oral
Long-term fluctuations of chum salmon and Pacific herring populations in Hokkaido
during 1883-2000
Masahide Kaeriyama
Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, 041-8611, Japan. E-mail: salmon@fish.hokudai.ac.jp
PICES Working Group 16 presents the impacts of climate and climate change on the key commercial species in
subarctic Pacific. Long-term population dynamics of chum salmon (Oncorhynchus keta) and Pacific herring
(Clupea pallasii) in Hokkaido were compared in relation to impact of climate trends, inter-specific interaction,
fisheries, and hatchery program. For the sustainable fisheries management of both species, a management
framework should be proposed that addresses four elements: inter- and intra-specific interaction, ecosystembased approach, climatic indicator, and coordinated action plan for fisheries and hatchery programs.
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PICES XV
W2-3232
Oral
Evidences of climate-induced impacts on key commercial species around Korean waters
Jae Bong Lee1, Suam Kim2, Chang-Ik Zhang2, Jin-Yeong Kim1 and Sukyung Kang1
1
2
National Fisheries Research and Development Institute, 408-1, Shirang-ri, Gijang-up, Gijang-gun, Busan, 619-902, Republic of Korea
E-mail: leejb@nfrdi.re.kr
Pukyong National University, 599-1, Daeyeon 3-dong, Nam-gu, Busan, 608-737, Republic of Korea
This paper presents the evidence of climate-induced impacts on productivity of key commercial species and
their fisheries around Korean waters, based on decadal scale and ENSO scale variability. The warming trend
after the 1976 and 1988 climatic regime shifts (CRS) was associated with a decline in cold-water species (e.g.,
walleye pollock) and an increase in warm-water species (e.g., common squid, jellyfish, mackerels). After the
1988 CRS, shared region in distribution between Jack mackerel and common mackerel decreased. These shifts
in the habitats of common squid and Jack mackerel resulted in changes in habitat areas of Pacific sardine and
mackerel. Also, a recent cooling phenomenon after 1998 was associated with an increase in cold-water species
(e.g., Pacific cod, herring) in Korean waters. We discuss plausible management plans around Korean waters
assuming climate change effected on the productivity and distribution of such species.
PICES XV
W2-3204
Oral
Trends in Russian fisheries in the North Pacific in relation to basic stock conditions and
their variability under the climate change
Vladimir I. Radchenko
Sakhalin Research Institute of Fisheries and Oceanography, 196 Komsomolskaya Street, Yuzhno-Sakhalinsk, 693023, Russia
E-mail: vlrad@sakhniro.ru
Fishing expeditions in the Russian far-eastern seas have traditionally used trawls tocatch fish. Trawl fisheries
accounted for the largest proportion of the Russian catch in the North Pacific and the following species
dominated the trawl catch: walleye pollock, herring, Pacific cod, Commander squid. Most of the the
groundfishes were captured over the shelf and continental slope. In the last five years, fish species accounted
for 91.8% to 94.7% of the Russian catch. The species composition of pelagic fish catch (walleye pollock 51.8%, herring - 11.7%, pink salmon – 8.2%, Pacific saury – 3.1% of total fishery harvest) appears to be
sensitive to climate change impacts. It is possible to predict future abundance of fish conditioned on
periodically fluctuating large-scale climatic factors and factors manifesting lasting trends, possibly, because of
the lower variation frequency. Future trends in species composition were predicted under assumptions
regarding the recurring regime shifts. These forecasts indicate that walleye pollock and Japanese sardine stocks
will increase in the third decade of the present century. The Pacific cod stock dynamics (3.2% of total) is
similar to pollock. Trends in pink salmon catch and abundance are expected to increase in response to an
increase in the heat budget of the upper layer of ocean. The catches of other salmon species (sockeye - 1.3%,
chum - 1.6% of total) are expected to remain stable. Crab stocks (red king crab – 0.4%, Snow crab – 0.7%)
were strongly exhausted by fishery, but they are expected to continue to play important role because of the high
market cost.
PICES XV
W2-3122
Oral
The potential effects of including/excluding environmental factors into stock
assessments
Michael J. Schirripa1 and J.J. Colbert2
1
2
Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, 2032 Southeast OSU Drive, Newport, OR,
97365, U.S.A. E-mail: Michael.Schirripa@noaa.gov
Cooperative Institute for Marine Resources Studies, Oregon State University, 2032 SE OSU Drive, Newport, OR, 97365, U.S.A.
The PICES Working Group 16 report on the impacts of climate and climate change concluded that climate is a
major factor affecting the productivity of virtually all key commercial species. However, almost none of the
stock assessments conducted on these species explicitly include climate effects in the assessment model. The
objective of this investigation is to evaluate the potential effects that the absence of climate variability in an
assessment has on the estimation of stock status and the conservation benchmarks used to manage a stock.
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Using biological and environmental parameters based on 2005 assessment of U.S. west coast sablefish, we use a
data simulator (FSIM) to produce data sets where recruitment of age-0 fish is explicitly driven by a known
environmental effect. We then analyzed these simulated data sets with the stock assessment software currently
in use on most of the west coast groundfish stocks (Stock Synthesis II) in ways that both omit and explicitly
include an environmental effect on recruitment. The resulting estimates of simulated parameter values,
conservation benchmarks, and stock status were then compared to the true underlying values used in creating the
simulated data sets. This comparison highlights the consequences, if any, of omitting climate variability from
model specification when, in fact, a relationship between climate and stock productivity exists.
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