JFM 2001 Quarterly Rpt. sidebar
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(Quarterly
Report for Jan-Feb-Mar 2001)
Socioeconomic
Assessments Program:
Modeling the Effect of Fishery Attributes on
Participation Rates and Angler Welfare
Changes in sportfishing trip attributes, such as
cost, harvest regulations, environmental quality,
and resource abundance, affect both the expected net
benefits associated with a fishing trip and
participation decisions. The ability to
estimate both of these is important for various
types of policy analysis. The study completed
by Drs. Todd Lee, Mark Herrmann (University of
Alaska, Fairbanks), and Keith Criddle (Utah State
University) and Charles Hamel (University of Alaska,
Fairbanks), uses hybrid stated preference questions
of anglers who sport fished in the marine waters off
the Kenai Peninsula, Alaska to estimate a nonlinear
random effects probit model that expresses both
participation rates and angler net benefits as
functions of trip attributes. The use of
stated preferences data along with a nonlinear
utility specification allows for the simulation of a
wide range of policy scenarios. The study
design and nonlinear model permit the identification
of substitution and complementary effects across
attributes, as well as non-linear marginal utility.
Econometric Analysis
of Stated Preference Ratings Data
Economic valuation and market research surveys often
ask respondents to rate a set of multi-attribute
alternatives. Economic choice theory is based
upon ordinal preferences, but standard estimation
approaches for ratings data are based upon
inter-personal utility comparisons. Developing
an ordinal model for ratings data has proven
difficult due to “tied” ratings. Drs.
David Layton (University of California, Davis) and
Todd Lee developed a new preference estimation
approach based only upon the ordinal content of
ratings data. They showed how the ordinal
content of any respondent’s set of ratings can be
viewed as a censored ranking, developed a censored
rank-ordered econometric model, and applied it to a
ratings conjoint survey of recreational fishing.
Measurement of
Capacity, Utilization, and Economic Performance in
Alaska Groundfish Fisheries
Overfishing and excess capacity are two common,
undesirable, and related characteristics of
domestic, foreign, and international fisheries.
They are related in three ways. First,
they both are caused by the externalities stemming
from the problem of common property. These
externalities provide incentives for fishermen to
invest too much in fishing vessels and gear and to
catch too much fish. Therefore, if the fishery
management regime is not able to block these
perverse incentives or eliminate the externalities
that generate them, excess capacity and overfishing
often occur. Second, excess capacity can increase
the risk and potential level of overfishing. Third,
overfishing decreases stock abundance and the target
catch level and can, therefore, further increase
excess capacity.
The adverse effects of excess capacity have become
too severe to ignore, and there have been increased
national and international efforts to address the
problem of excess capacity. As part of this
effort, Congress passed the American Fisheries Act
(AFA) in 1998, which was, in part,an effort to
“rationalize” the Bering Sea-Aleutian Island
(BSAI) walleye pollock fishery (the most valuable of
the Alaska groundfish fisheries). The AFA
included regulations that restricted access to
certain parties and allowed formation of
cooperatives that instituted fishing rights which
could be traded among the members of the
cooperatives. Initial reports indicate that
there has been a decrease in fishing effort and an
increase in season length for the pollock fishery
since passage of the AFA. However, given that the
quantity of pollock caught has not diminished and is
still being taken in a few months time, it is
unclear whether observed capacity reductions are
sufficient to ease existing concerns. In order to
further our understanding of the issues discussed
above, Ron Felthoven estimated harvesting capacity
and utilization in the catcher processor sector of
the BSAI pollock fishery and analyzed the changes
brought about by the AFA. Two methods for measuring
fishing capacity – stochastic production frontiers
(SPF) and data envelopment analysis (DEA)– were
employed in multi-input, multi-output applications
to that sector of the fishery. The resulting
capacity estimates from the models were then
compared and used to characterize the degree of
excess capacity in this fleet and to illustrate the
substantial differences in capacity estimates that
may arise when the stochastic aspects inherent in
harvesting technologies are ignored. And,
because DEA and SPF models allow one to analyze
technical efficiency in production, the frameworks
were also used to compare pre- and post-AFA
efficiency among individual vessels and the fleet as
a whole. Ron Felthoven completed this
dissertation research as one of the first four
Fellows in the NMFS/Sea Grant Graduate Fellowship
Program in Population Dynamics and Marine Resource
Economics.
Age and Growth Program
Estimated production figures for
1 January 2001 to 31 March 2001.
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Walleye pollock
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6,760
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Sablefish
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1,302
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Pacific whiting
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1,117
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Northern rockfish
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1,240
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Light dusky rockfish
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186
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Total production figures were 10,605 with
2,055 test ages and 61 examined and
determined to be unageable.
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Other
Research
Dr. Todd Lee has received a grant for $95,000 from
the NMFS Office of Science and Technology to study
the economic effect of bag limits and
catch-and-release fishing regulations. The
study will measure the importance of harvest limits
on angler participation decisions and the economic
value anglers derive from a recreational fishing
trip. The data for the study will be gathered
from a survey that will be administered this fall.
The final results are expected to be available
by August 2002.
By Joe Terry.
U.S. North Pacific Groundfish
Observer Program:
Training, Briefing and Debriefing Statistics
During the first quarter of 2001, 314 observers were
trained, briefed, and equipped for deployment to
fishing and processing vessels and shoreside plants
in the Gulf of Alaska, Bering Sea, and Aleutian
Islands region. They sampled aboard 270
fishing and processing vessels and at 22 shoreside
processing plants. These observers were
trained or briefed in various locations. The
University of Alaska Anchorage (UAA) Observer
Training Center trained 38 first time observers and
another 182 observers with prior experience were
briefed at this site. The AFSC Observer
Program in Seattle briefed another 86 observers who
had prior experience. Eight observers were
excused from briefing because they had just
completed a cruise successfully and were returning
immediately to the field. The first quarter
2001 observer workforce thus comprised 12% new
observers and 88% experienced observers.
The Observer Program conducted a total of 51
debriefings during the first quarter of 2001. Four
debriefings were held in Kodiak, 17 in Anchorage,
and 30 were held in Seattle.
Observer Program Hosts
National Safety Training
Fishery observer trainers from each NMFS region
gathered at the Center in March to attend a safety
training course, designed specifically for
teachers of sea safety. The purpose of the
course was to ensure that NMFS staff, who are
responsible for training fishery observers, have the
expertise and resources necessary to provide the
best possible safety training for the gear and
vessel types they monitor. The 5-day course, taught
by the Alaska Marine Safety Education Association,
was intense, running well into the evenings, and
packed with information on safety equipment, safety
techniques, and ways to teach safety to observers.
On the sixth day, the NMFS observer trainers
met for discussion about their own program’s
training needs and ways to share resources.
Observer Program Cadre Opens
The Observer Program began full implementation of
its cadre during the first quarter of 2001. The
cadre consists of five new employees hired in
December 2000 along with two other staff members
stationed in new office space in the Federal
building annex in Anchorage. The cadre is an
inherently flexible unit of employees that can be
deployed as needed to ports throughout Alaska.
They help to increase the Observer Program’s
presence in the field and allow for more “front
line” communication between NMFS, observers, and
the fishing industry. Todd Loomis, the
Anchorage field office manager, is responsible for
leading the cadre.
By Bob Maier
Status of Stocks and
Multispecies Assessment Program:
Korean Workshop on Large Marine Ecosystems
Jim Ianelli was invited to present a paper at the
“Korean Yellow Sea Large Marine Ecosystem
(K-YSLME) Workshop” on Jeju Island, South Korea.
Ianelli presented a paper titled: “Fisheries
management of eastern Bering Sea pollock in an
ecosystem context.” Representatives from
several research and management organizations within
Korea participated in the workshop, as well as
invited speakers from the United States and
China.
Working group sessions were held in the areas of
pollution, geographic information systems (GIS),
fisheries management, and oceanographic
productivity. Guidelines for group discussion
were to review findings of K-YSLME and point out
where further developments and analyses were needed.
Recommendations specific to the fisheries
working group were to
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Continue trawl surveys with a
view to establish a times series,
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Increase the trawl survey
sample stations in area (to the west, east and
south) and density,
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Contrast results from surveys
with available historical surveys and commercial
fishing information,
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Continue to experiment with
trawl gear (e.g., use of cover net with video
for selectivity estimates), and hydroacoustic
equipment (e.g., target strength measurements,
adaptive sampling),
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Add a midwater trawl to
verify acoustic data used for echo-integration
estimates of stock abundance,
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Investigate methods for
examining carrying capacity in the Yellow Sea,
such as using ECOSIM and comparing
productivity in other similar ecosystems around
the world,
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Use separate vessels for fish
surveys and the collection of oceanographic
data.
Resource Ecology and
Ecosystems Modeling Program
A total of 1,018 fish stomachs were collected from
the eastern Bering Sea and 992 from the Gulf of
Alaska. Laboratory analysis was performed on 1,009
groundfish stomachs from the eastern Bering Sea, 47
from the Gulf of Alaska/Aleutian Islands, and 626
from the Washington-Oregon-California area. No
observers returned stomach samples during the
quarter.
North Pacific Basin Models
Kerim Aydin was a key participant in a workshop
sponsored by the Basin Ecosystems (BASS) Task Team
of the North Pacific Marine Science Organization
(PICES), held on 5-6 March 2001, in Honolulu,
Hawaii. The workshop was hosted by the NMFS Honolulu
Laboratory. Twelve scientists from five
countries, the United States, Canada, Russia, Japan,
and China, attended the workshop. The purpose
of the meeting was to exchange data and develop two
food web models of the eastern and western North
Pacific subarctic gyres for the purpose of examining
ecosystem structure and function, climate impacts,
and the historical effects of fishing on the pelagic
community of the two ecosystems.
The model focused on the subarctic Pacific, north of
45°N and south of the continental shelf, divided
into eastern and western sections by the narrowing
of the subarctic Gyre along the Aleutian Island
chain. This area is high in primary production
relative to the adjacent subtropical waters and
represents extremely important feeding grounds for
Pacific salmon (Oncorhynchus spp.), many large squid
species, and marine mammals. Changes in the
circulation and production of the gyres are linked
to regime shifts as typified by the Pacific Decadal
Oscillation, which is considered to have a large
impact on salmon growth and survival and is
important to evaluate relative to other impacts of
climate change.
Extensive data exchange occurred between countries
in the month before the workshop. Previously
unavailable data was assembled, including fishing
rates, biomass, production rates, and diet habits of
over 60 distinct species or guilds of organisms
living in the region, representing the entire
trophic web. The preliminary estimation of the
overall flow of biomass within the system was
assembled by Kerim Aydin using this data and
presented at the workshop.
At this stage, the results were aimed at identifying
key species for which little data were available.
These species included micronektonic squid,
forage fish, and mesopelagic fish, species which
provide the primary conduits of energy from primary
production to salmon and higher trophic levels.
Methods for linking fish and mammal production
to climate via lower trophic-level (plankton)
modeling was also discussed. Based on this
preliminary information, the model was distributed
to allow researchers to focus on specific
data-gathering and refinement tasks, to be presented
at the 10th Annual PICES Meeting in October 2001.
At that point, the final product will be
evaluated as a tool for investigating the effects of
climate change on the North Pacific gyre ecosystems.
Climate Change and
Biodiversity
Pat Livingston organized and chaired a workshop,
sponsored by PICES, the Sloan Foundation’s Census
of Marine Life (CoML), and the International Pacific
Research Center (IPRC), held 7-9 March 2001 at
the East-West Center in Honolulu. The workshop,
“Impact of Climate Variability on Observation and
Prediction of Ecosystem and Biodiversity Changes in
the North Pacific,” gathered 63 marine scientists
including physical, chemical, and biological
oceanographers, atmospheric scientists, and fish,
marine mammal, and bird researchers from Canada,
China, Japan, Korea, Russia and the United States.
The workshop focused on reviewing the goals and
strategies for observing North Pacific marine
ecosystems and their biodiversity and improving our
ability to predict ecosystem change. This was
accomplished by 1) defining our existing
observation and prediction system (regional and
basin-scales), 2) identifying needed improvements to
the existing system for increasing our understanding
of biodiversity and climate-linked changes in
biodiversity, and 3) nominating existing time series
and predictions for inclusion into a PICES Ecosystem
Status Report. Workshop participants were
primarily representatives of various national
monitoring and prediction programs or members of
various PICES groups or programs. Existing
time series observations on physical and chemical
oceanography and climate; phytoplankton,
zooplankton, and micronekton; fish and crustaceans;
and marine mammals and birds from the eastern,
western, and open North Pacific were presented at
the workshop by participants. Although the
workshop’s primary emphasis was on time series
information, candidate predictive models (from
purely physical to coupled biophysical models) were
also identified for use in forecasting future
climate changes and their effects on biota.
Major workshop recommendations included adding these
time series data to a North Pacific ecosystem
metadatabase that was originally started by NOAA
researchers Allen Macklin and Bern Megrey to
facilitate Bering Sea research and to begin work on
structuring and compiling a North Pacific Ecosystem
Status Report. The final workshop report is being
prepared and is targeted for completion by fall
2001.
By Pat Livingston.
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