Download S4-All - North Pacific Marine Science Organization

October 24, 09:05 (S4-9552)
Climate variability and Interacting Trophic Control in the Southern California Current
Martin Lindegren1, David M. Checkley, Jr., Mark D. Ohman, Anthony J. Koslow and Ralf
Goericke
1
Technical University of Denmark, Charlottenlund, Denmark. E-mail: [email protected]
The degree to which ecosystems are regulated through bottom-up (resource-driven) or top-down
(consumer-driven) processes represents a long-standing issue in ecology, with important
consequences for resource management and conservation. In marine ecosystems, the role of
bottom-up and top-down forcing has been shown to vary over spatio-temporal scales, often
linked to highly variable and heterogeneously distributed environmental conditions. Ecosystem
dynamics in the Northeast Pacific have been suggested to be predominately bottom-up regulated.
However, it remains unknown to what extent top-down regulation occurs, or whether the relative
importance of bottom-up and top-down forcing may change in response to climate variability. In
this study, we investigate the effects and relative importance of bottom-up and top-down forcing
during changing climate conditions on the food-web dynamics of the Southern California
Current System (SCCS) using a generalized food-web model. This statistical approach is based
on non-linear threshold models and a unique long-term data set (~60 year) covering multiple
trophic levels from plankton to predatory fish. We show evidence of strong bottom-up regulation
throughout the food-web, interacting with moderate top-down forcing, but only during periods of
low nutrient availability and productivity, such as occurring during El Niño events. Furthermore,
we highlight potential concerns for marine and fisheries management by demonstrating increased
sensitivity of pelagic fish to exploitation during unfavorable climate and feeding conditions.
October 24, 09:30 (S4-9562)
Big YES to sustainable ecosystem management and why NO to sustainable monitoring
efforts? – Gap between demand and supply in Japanese case
Sanae Chiba
JAMSTEC, Japan. E-mail: [email protected]
The world oceans and ecosystem today are exposed to multiple environmental stressors, such as global
warming, ocean acidification, hypoxia and direct human activities. As a better understanding of responses
of ocean biogeochemistry and the ecosystem to these threats is crucial for sustaining ecosystem services
for human society, there is an increasing demand in establishing regional to global ocean observing
systems and research networks. In reality, however, it is not easy to sustain such observing efforts, in
many cases due to the limitation of resources, and Japan is not an exception. In June 2014, we had the
workshop “Toward the Better Collaboration between Scientists and Policy Makers” in Tokyo, funded by
the University of Tokyo through its research project, “New Ocean Paradigm on Its Biochemistry,
Ecosystem and Sustainable Use (NEOPS)” (http://ocean.fs.a.u-tokyo.ac.jp/index-e.html) and the
“Science, Technology, and Innovation Governance” program at the Graduate School of Public Policy
(http://stig.pp.u-tokyo.ac.jp/). The goal of the workshop was to define the major obstacles in their
communication and seek a better strategy to facilite collaboration between scientists and policy makers in
Japan, particularly to promote future ocean research. Talks and discussion occurred with invited experts
from various areas in the natural and social sciences, science policy, public relations, and NGOs. This
presentation is to report on the summary and outcome of the workshop.
October 24, 09:50 (S4-9671)
Design of ocean observation systems: Sampling requirements to monitor fish population
and community trends as Essential Ocean Variables
J. Anthony Koslow and Melaina Wright
Scripps Institution of Oceanography, University of California SD, La Jolla, CA, USA. Email: [email protected]
Essential ocean variables for observing ocean ecology must be selected on the basis of their
maturity, societal benefit, relevance to ocean health, and ease/cost of observations. Fish
communities are a highly-valued component of marine ecosystems and are sensitive to natural
environmental variability and a range of human stressors: overfishing, habitat loss, pollution and
eutrophication, and potentially ocean acidification and deoxygenation. Fishery statistics are
collected widely but are limited to commercial species and are subject to bias. Ichthyoplankton
surveys serve to monitor regional fish communities by sampling when most species are
vulnerable to capture by simple gears (plankton nets), including commercial and non-commercial
taxa, and taxa inhabiting coastal and oceanic, epi- and mesopelagic, demersal, and reef habitats.
However, fish eggs and larvae are patchily distributed and do not dominate plankton samples, so
it is unclear whether limited sampling programs would adequately capture trends in larval fish
abundance.
To test this, we sub-sampled the CalCOFI data set to assess whether sampling a single transect or
fraction of a transect would capture the trends exhibited by key species or multivariate patterns
observed in the full data set. Time series of abundance for common fish species based on a single
onshore-offshore transect were generally significantly correlated with those from the full data
set, with the variance explained related to the number of sampling stations. Similar multivariate
patterns of community change were observed between the full and reduced data sets, with the
correlation again related to sample size.
October 24, 10:10 (S4-9577)
Understanding the mechanisms of the interannual variability of
phytoplankton in the Ulleung Basin, East Sea: A modeling study
Soonmi Lee1,2, Sinjae Yoo1,2, Chanjoo Jang1,2 and M. Butenschon3
1
School of Ocean Science and Technology, Korea Maritime and Ocean University, Busan, R Korea
E-mail: [email protected]
2
Marine Ecosystem Research Division, Korea Institute of Ocean and Science, Ansan, R Korea
3
Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, UK
We investigated the seasonal dynamics of phytoplankton responding to the changes in the mixed
layer depth and volume transport of Tsushima warm current in the Ulleung Basin for the years
2001-2012. To address the role of vertical mixing and advection on interannual variability of
phytoplankton communities, we used a zero-dimensional European Regional Seas Ecosystem
Model (ERSEM). We compared the years of deep winter mixing with the years of shallow winter
mixing during the period. The model results showed that the deep winter mixing increased the
nutrient supply to the upper layer. It led to a better growth of diatoms. On the other hands, the
shallow winter mixing advanced the initiation of spring blooms of diatoms because of enhanced
light availability but reduced the production in spring by poor nutrient supply. Also the model
indicated that the nutrient supply by advection plays an important role in regulating the
phytoplankton blooms and control of the nutrient drawdown in summer. These results suggest
that in the Ulleung Basin, the balance between the vertical mixing and the advection process can
induce a large shift in phytoplankton communities. We discuss the implication of this results in
light of climate change.
October 24, 10:50 (S4-9423)
The role of plankton time-series in managing our seas in a climate of macroecological
change
Abigail McQuatters-Gollop
Sir Alister Hardy Foundation for Ocean Science, UK. E-mail: [email protected]
Unprecedented basin-scale ecological changes are occurring in our seas. As temperatures warm ocean pH is
lowering, sea ice is decreasing, and marine stratification and nutrient regimes are changing. We are only just
beginning to understand the ecological manifestations of these climate alterations and their consequences for marine
management. The management of our seas towards a healthy state will therefore take place against a background of
large-scale climate-driven macroecological change, which must be considered when developing indicators and
setting environmental targets. Much of our knowledge of macroecological change in the North Atlantic is a result of
research using data gathered by the Continuous Plankton Recorder (CPR) survey, a near-surface plankton
monitoring program which has been sampling in the North Atlantic since 1931. CPR data indicate that North
Atlantic and North Sea plankton dynamics are responding to both climate and human-induced changes, presenting
challenges to the development of pelagic indicators and targets for achievement of good environmental status in
European Seas. Long-term ecological time-series, such as the CPR, further our understanding of ecological response
to climate and anthropogenic drivers, providing evidence to inform and support the sustainable management of
marine waters through policy mechanisms.
October 24, 11:15 (S4-9721)
The North Pacific Continuous Plankton Recorder survey
Sonia Batten
Sir Alister Hardy Foundation for Ocean Science, Nanaimo, BC, Canada
E-mail: [email protected]
The North Pacific CPR survey was a PICES initiative, developed from the 1998 MONITOR Technical
Committee Meeting’s desire to address the lack of open ocean plankton sampling in the North Pacific.
While much shorter than the North Atlantic CPR survey the North Pacific survey is now in its 15th year of
sampling. During this time-span the north-east Pacific has seen unusually high-frequency variability in
ocean climate with the warmest and coldest years of the last several decades occurring only 3 years
apart, offering a challenge to marine resource managers. This presentation explores some of the
strengths of this monitoring program, for example; 1.That the ocean-climate variability is readily
detected in the plankton data both in terms of timing and composition changes. 2 That the survey
provides a link between the regionally-focused national sampling programs, an aspect that could be
further exploited. 3 That the data are already included in regional assessments of use to resource
managers. The presentation will also include a discussion of some of the added-value components of the
survey, such as the instrumentation fitted to the CPR and the sample archive now being exploited for
molecular analyses. These have the potential to generate new insights and greater applicability of the
program in the future.
October 24, 11:35 (S4-9666)
How the 20 year Newport Line zooplankton time series is used to inform fisheries
management
William Peterson1, Jay Peterson2, Jennifer Fisher2 and Cheryl Morgan2
1
NOAA-Fisheries, Northwest Fisheries Science Center, Hatfield Marine Science Center, Newport, OR, USA
E-mail: [email protected]
2
Cooperative Institute for Marine Resources Studies, Hatfield Marine Science Center, Oregon State University,
Newport, OR, USA
Through fair weather and foul, the Peterson lab has gone to sea fortnightly since 1996, mostly on
small research vessels (length 12-17m), to study seasonal and interannual variations in the
physical drivers of pelagic ecosystem change in the coastal upwelling zone in the northern
California Current (NCC). Seven stations are sampled along a transect (44.6°N) that spans
continental shelf and slope waters off Newport Oregon. Standard parameters measured include
water column profiles of temperature, salinity, fluorescence and oxygen, water samplings for
nutrients, chlorophyll and phytoplankton species composition, and plankton net tows for
zooplankton, krill and fish eggs and larvae. Several ecological indicators have been produced
from these time series data which characterize the bioenergetics of the food web: biomass of
northern and southern copepods which are indicators of ‘lipid-rich’ and ‘lipid-depleted’ food
chains, respectively. Significant correlations are found between the copepods and salmon returns
(coho and Chinook salmon), rockfish, sablefish, and lamprey as well as recruitment of mole
crabs (Emerita) and the invasive European green crab. These findings are of interest to managers
because the information reveal mechanisms on how basin-scale climate drivers such as the PDO
and ENSO affect many fisheries in the NCC, by providing early warning of future recruitment
variability and by providing a unique view of how variable ocean conditions affect the pelagic
marine ecosystems. However the data are not yet used directly in management because our work
is a “research time series” and not an ”operational time series”, and thus one that could end at
any time.
October 24, 11:55 (S4-9752)
Long term zooplankton monitoring and database programs in British Columbia –
understanding the dynamics of a changing ocean
Moira Galbraith1, David Mackas1 and R. Ian Perry2
1
Fisheries & Oceans Canada, Institute of Ocean Sciences, Sidney, BC, Canada
E-mail: [email protected]
2
Fisheries & Oceans Canada, Pacific Biological Station, Nanaimo, BC, Canada
Zooplankton monitoring is very important in providing early indications of changing ocean
conditions because of short time lags and closer connections with physical processes, compared
with fish populations. The Department of Fisheries and Oceans (DFO) has been collecting
biological oceanographic samples as part of various historical and ongoing monitoring programs
off the west coast of British Columbia, Canada since the late 1970’s. The majority of
zooplankton data were held in numerous archives, computer tables, tech reports and raw count
sheets in filing cabinets. In recognition of the difficulty in using or even accessing the data the
Zooplankton Database was developed at the Institute of Ocean Sciences in 1997. We describe
how this database has grown to include over 22178 samples and 1228 species representing 5643
taxonomic categories, back to 1956 (Stn. P. weather ship). It contains useful features that are
sometimes not incorporated in other zooplankton archives, such as separate life stages and/or
size classes within species, the ability to multiply abundance by body size to estimate biomass
within taxa and the capability to roll-up abundance or biomass across life stages or species into
broader taxonomic groups. This “low-level” (e.g. life stage) information is much more important
for models of predator-prey interactions that use size-based approaches, compared with speciesbased feeding relationships. We also discuss the difficulties and limitations in comparing time
series across temporal and spatial changes plus shifting priorities in analyses and taxonomic
resolution. The development of this database has enabled analyses and summaries of these data
to contribute regularly to DFO activities, including the State of the Ocean reviews, salmon
survival dynamics, and indicators of ecosystem conditions.
October 24, 12:15 (S4-9734)
Taking stock
David M. Checkley, Jr.
Scripps Institution of Oceanography, University of California, San Diego, CA, USA
E-mail: [email protected]
Time series of observations are necessary to understand the past dynamics of systems and predict their
future states. Disciplines as disparate as finance and fisheries rely on predictions, hence time series, as the
basis for decisions on management and policy affecting their respective stocks. Why, then, are plankton
time series so difficult to maintain funding for? I will draw on plankton time series from major fisheries
oceanography programs in the world to illustrate their value for making decisions in management and
policy. Their value scales with their duration, such that they become increasingly relevant to large-scale
phenomenon such as ecosystem degradation and climate change, and thus their value transcends their
intended use for fisheries management to use in environmental policy. I argue that this increased value
should justify continued, if not greater, investment in such observing programs while acknowledging the
limits of our ability to understand and predict stock dynamics.