PICES Press Vol. 22, No. 2

North Pacific Marine Science Organization

OSM Sessions on “Ecosystem status, trends, and forecasts” and“Ecosystem resilience and vulnerability”
by Thomas Therriault and Hiroaki Saito
to trends, she used subtropical monitoring sites (BATS andHOT) to show that with increased warming, the biologicalpump is changing. Lastly, she argued the importance ofunderstanding the mechanisms responsible for change aswell as documenting changes in status and trend.

Marine ecosystems are constantly changing. Therefore,
researchers need to develop and to communicate
information on ecosystem status, trends, and forecasts toensure that sound management and policy decisions are
made for the benefit of the societies that depend on them.
Ecosystem indicators are one way to communicate suchinformation, but the selection of the most appropriate
indicators can prove challenging, especially given an
increasingly complex array of audiences. It is likely thatdifferent indicators will be needed where the scale ofecosystem responses to different stressors must bereconciled with the scale of the perturbation (e.g., coastal
versus oceanic). Forecasting ecosystem change demands
good understanding of how multiple stressors affectecosystem structure and function. A key element of theFUTURE program is the ability to convey to diverse
audiences, in each of the PICES member countries,
ecosystem status, trends and forecasts. Session S4 on“Ecosystem status, trends and forecasts” explored current
and proposed ecosystem status and trend indicators,
including some already in use in the North Pacific
Ecosystem Status Reports, and attempted to identify
metrics required in support of ecosystem forecasts.
The plenary speaker, Dr. Deborah Steinberg, did an
excellent job setting the stage for this topic session by
giving a talk entitled “Ecosystem comparison of trends inzooplankton community structure and role inbiogeochemical cycling”. She presented an overview ofthe status of spatial variation in zooplankton biomass andimplications for the biological pump that can becharacterized by community structure. She then highlighted
patterns of eutrophic and oligotrophic regions and provided
links to climate indices or sea ice dynamics. With respect

In the breakout session there were talks by Drs. Sanae
Chiba and Sonia Batten that demonstrated how long-termzooplankton data sets could be analysed to find trends andpatterns with respect to distribution. Dr. Chiba showed thatthe diversity index was correlated with the Kuroshio
Extension Current strength (1960–1988), but that thisrelationship broke down during the oceanographic regime
shift that followed this period. Dr. Batten explained how
various indices obtained from Continuous Plankton
Recorder (CPR) samples, such as the phytoplankton colour
index, total diatom biomass, timing of the spring diatom
bloom, warm-water copepod abundance, etc., could
indicate ecosystem regime shifts. Talks by Drs. Douding
Lu and Ichiro Imai assessed the trends and status ofharmful algal blooms (HABs) by means of retrospective
analysis of HAB data sets. Dr. Lu showed how increasing
HAB events in Chinese coastal waters were related toincreasing anthropogenic activity, such as eutrophication,
ballast water, or aquaculture. Similarly, Dr. Imaidemonstrated how new water quality regulations reduced
eutrophication, improved water quality in the Seto InlandSea, Japan, and decreased the number of HAB events. The
session also had talks about status, trends, and forecasts forhigher trophic levels. Dr. Jongjun Tian suggested an
ecological indicator as an early warning signal forforecasting the future (current) regime shift. He was able
to demonstrate how fish assemblage data were used todetect five past regime shifts (1911, 1934, 1963, 1975 andS4 plenary speaker, Dr. Deborah Steinberg, addressing session participantson ecosystem cross-comparisons of zooplankton communities.

S4 speaker, Dr. Ichiro Imai, discussing long-term trends of red tides andtoxic blooms in the Seto Inland Sea of Japan.

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North Pacific Marine Science Organization

PICES Press Vol. 22, No. 21988) and that these coincided with shifts in sea surface
temperature and a climate index. Dr. Jon Brodziak used a
striped marlin dataset to introduce participants to a new“steepness” index which can quantify population resilience,and be used to set biological reference points, such as
maximum sustainable yield. Drs. Haruka Nishikawa andSuam Kim talked about ways to develop fishery forecasts
for commercial target species (neon flying squid, Pacificflying squid) under global warming scenarios. Lastly, Dr.
Hiroaki Saito’s talk provided a nice summary of the session
by considering mechanisms of fish species alternation in
the western North Pacific which were induced by changes
in the wind field in the central-eastern North Pacific. He
pointed out the weaknesses of fisheries as a modern
industry, i.e., unplanned high variability, and that
forecasting future changes in marine ecosystem andfisheries production is likely the most effective way tomitigate intrinsic weaknesses in modern fisheries. Clearly
our understanding of the mechanisms creating observed
ecosystem variation is still limited. Much remains to be done
to “understand the mechanisms behind status and trends”
and to “forecast future states”, as these are essential science
contributions to society.

S6 plenary speaker, Dr. Beth Fulton, chatting with Robin Brown during
coffee break.

Marine ecosystems around the globe are affected bynumerous natural and anthropogenic stressors.
The
interactions among stressors are incredibly complex andproving difficult to understand. Ultimately, these stressors
will change ecosystem structure and function. This canlead to changes in ecosystem stability and productivity, andimpact the societies that depend on them. One of thecentral themes of the FUTURE Science Plan focuses on
ecosystem resiliency and vulnerability to natural andanthropogenic stressors and poses the question how
ecosystems around the North Pacific might change in thefuture. Thus, the ability to understand how resilient marine
ecosystems are and to characterize the degree to whichecosystems are vulnerable to change via multiple stressors
is critical to advancing the FUTURE program. Session S6
on “Ecosystem resilience and vulnerability” attracted onlya single submitted oral presentation, perhaps indicating thedifficulty in quantifying resilience and vulnerability inmarine systems with diverse stressors. Because of thisproblem, there has been little attention devoted to theseissues to date in PICES. Dr. Beth Fulton exploredresilience in a plenary talk titled “Exactly how resilient areecosystems?”.

Dr. Hiroaki Saito providing the final talk of Session S4.

Dr. Thomas Therriault (Thomas.Therriault@dfo-mpo.gc.ca) is a Research Scientist with Fisheries andOceans Canada (DFO) at the Pacific Biological Station in Nanaimo, British Columbia. Tom is working on anumber of aquatic invasive species research questions both within DFO and through the second CanadianAquatic Invasive Species Network (CAISN II). He was the Principal Investigator for the Taxonomy Initiativeof PICES Working Group 21 on Non-indigenous Aquatic Species that includes rapid assessment surveys for
non-indigenous species. Within PICES, Tom now serves as Chairman of Science Board.

Dr. Hiroaki Saito (hsaito@aori.u-tokyo.ac.jp) is an Associate Professor at the Atmosphere and Ocean
Research Institute, the University of Tokyo. He has a broad range of interests but his focus lies in the role ofmarine organisms in food-web dynamics and biogeochemical cycles. He is one of the establishing membersof the A-line monitoring programme for the western North Pacific. He was a core member of the SEEDS I, IIand SERIES Fe fertilization experiments, led the DEEP (2002 2007), SUPRFISH (2007–2012) projects, andis leading the SKED project (2011–2021). He has also been involved in IMBER, and was Chairman ofIMBER-Japan from 2004–2008. In PICES, Hiroaki has been a member of several expert groups. He iscurrently a member of the BIO Committee and SG-SC-NP, is Chairman of the FUTURE AP-COVE, and isVice-Chairman of Science Board.

17Summer 2014