Download ICES Working Group on Zooplankton Ecology meet in Riga, Latvia

GLOBEC INTERNATIONAL NEWSLETTER OCTOBER 2007
presence of noise in both measurement and environment. The
workshop concluded with a number of specific recommendations
for changes in:
• productivity regimes that require adapting management
procedures or procedures robust to regimes,
• habitat influencing measurement and stock carrying capacity
• growth and maturation influencing short and medium term
advice, and
• recruitment changes due to environmental influence in the
short and medium term.
Recommendations also include the use of multi-species models
primarily for hypothesis testing and testing management
procedures. Finally the group recognised the need for longer
term prediction and thus for developing climate scenarios for
sensitive areas such as the Baltic Sea.
The report of the meeting is available through the ICES
(http://www.ices.dk/reports/ACFM/2007/WKEFA/WKEFA_2007.pdf)
and the EUR-OCEANS Knowledge Transfer websites
(http://www.eur-oceans.eu/training_and_outreach/wp9/).
ICES Working Group on Zooplankton Ecology meet in Riga, Latvia
Roger Harris
Plymouth Marine Laboratory, Plymouth, UK ([email protected])
Held from 26-29 March 2007, the meeting of the ICES Working
Group on Zooplankton Ecology (WGZE) was the largest meeting
so far of the group. The meeting, chaired by Astthor Gislason
(Marine Research Institute, Reykjavik) was hosted in Riga, Latvia
at the kind invitation of Solvita Strake from the Institute of Aquatic
Ecology and was attended by 30 scientists representing 14
countries (Fig 1). This article provides a short summary of the
discussions and outcomes. The full report of the WGZE meeting
can be found at: http://www.ices.dk/iceswork/workinggroups.asp
Some highlights of the WGZE discussions included:
•
•
•
In the North Atlantic, significant changes have occurred in the
abundance, distribution, community structure and population
dynamics of zooplankton and phytoplankton, mainly reflecting
changes in regional climate, caused predominantly by the
warming of air and sea surface.
The changes in the zooplankton and phytoplankton
communities which are at the bottom of the marine pelagic
food web, affect higher trophic levels, as the synchrony
between predator and prey (match-mismatch) plays an
important role (bottom-up control of the marine pelagic
environment) in the successful recruitment of top predators,
such as fish and seabirds.
Figure 1. Participants at the WGZE meeting in Riga.
in hydrodynamics and sea temperature. Considering the OSPAR
Climate Request the following evidence was provided of changes
in the plankton in relation to hydroclimatic changes:
•
The NAO has been rising over the past 30 years, as have the
surface water temperatures of the European continental shelf.
This has caused changes in the planktonic compartment
of the marine ecosystem affecting plankton production,
biodiversity, species distribution which has had effects on
fisheries production and other marine life (e.g. fish larvae
and seabirds).
•
In North Sea, the population of the previously dominant
zooplankton species (the cold water Calanus finmarchicus)
has decreased in biomass by 70%, between the 1960s
and the post 1990s. Warm-water species have moved
northwards to replace this species although their biomass
is not as abundant.
•
A shift in the distribution of many plankton and fish species
by more than 10° latitude northward has been recorded in
the OSPAR area over the past thirty years.
•
The seasonal timing of phyto- and zooplankton production
also altered in response to recent climate changes. This has
consequences for plankton predator species, including fish,
The poor recruitment of several fish of commercial interest
and the low seabird breeding productivity recorded in
recent years in some regions are associated with changes in
plankton biomass and in the seasonal timing of plankton.
In reviewing the ICES Annual Plankton Status Report (http://www.
ices.dk/pubs/crr/crr281/CRR281.pdf) various plankton trends and
changes were noted and important additions and improvements
to the report are planned.
When considering phenological changes several examples were
discussed (e.g. Acartia sp., Temora longicornis, Pleurobrachia
pileus, echinoderm larvae in the North Sea). Phenology is already
included in the ICES Annual Plankton Status Report and will be
expanded.
The WGZE had been asked to assess and report on changes
in the distribution, population abundance and condition of
zooplankton in the OSPAR maritime area in relation to changes
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GLOBEC INTERNATIONAL NEWSLETTER OCTOBER 2007
Zooplankton studies in the Baltic
During the Riga meeting a Baltic Sea Mini Session, which
included the following presentations of the work of the
regional research community.
Short overview of Baltic Sea activities
Piotr Margoński, Sea Fisheries Institute, Gdynia
National research programme climate change impact on
the water environment of Latvia
Andris Andrushaitis, Institute of Aquatic Ecology, Riga
Baseline port surveys for invasive marine species in the
north-eastern Baltic Sea
Solvita Strake, University of Latvia, Riga
Figure 2. Cercopagis pengoi, an introduced species of cladoceran, which
through its predatory activity has had a major impact on the plankton
community structure in Baltic. Photographs courtesy of Arno Põllumäe
and Julia Polunina (inset).
Trying to find out more (about marine mesozooplankton).
Anda Ikauniece, Latvian Institute of Aquatic Ecology,
Riga
whose life cycles are timed in order to make use of seasonal
production of particular prey species.
Monitoring of zooplankton in the SE Baltic
Natalja Demereckiene, Latvian Fish Resource Agency
•
In the North Sea and around the British Isles, considerable
increase in phytoplankton biomass has been recorded since
the mid-1980s.
Zooplankton in the south-east Baltic
Julia Polunina, P.P. Shirshov Institute of Oceanology,
Kaliningrad
•
In the North Sea functional changes in the phytoplankton
community have been recorded in recent decades, with
an increase of dinoflagellates and a decrease of diatom
abundance in response to warmer sea waters.
•
In the North Sea, warmer conditions earlier in the year together
with increased phytoplankton abundance since the late 1980s,
have determined the significant increase of meroplankton,
in particular echinoderm larvae of Echinocardium cordatum.
This change in the food web structure, due to the competitive
exclusion of the holozooplankton (i.e. permanent plankton
species) by the meroplankton, may significantly diminish
the transfer of energy towards top pelagic predators (e.g.
fish) while increasing the same transfer towards the benthic
component.
Hydrological regimes instability and climate changes
influence on zooplankton community of open parts of
the Baltic Sea and the Gulf of Finland
Larisa Litvinchuk, Zoological Institute of the Russian
Academy of Sciences, St Petersburg
•
Future warming is likely to alter the geographical
distribution of primary and secondary pelagic production,
affecting oxygen production, carbon sequestration and
biogeochemical cycling. These changes may place
additional stress on already-depleted fish stocks as
well as have consequences for mammal and seabird
populations.
Several examples of introduced species were noted from both
sides of the North Atlantic, most notably Mnemiopsis leydii that
has been observed in the Baltic Sea, the Kattegat and the North
Sea, and has extended to waters off Bergen.
The WGZE encouraged microzooplankton to be included in time
series monitoring within the ICES area.
Arrangements for the planning of the ‘Joint WGZE/CIESM
Workshop to compare Zooplankton Ecology and Methodologies
between the Mediterranean and the North Atlantic (WKZEM)’ (Co-
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Recent newcomers in zooplankton of Estonian coastal
areas
Arno Põllumäe, Estonian Marine Institute, Tallin
Zooplankton monitoring as it is carried out by FIMR
Juha Flinkman, Finnish Institute of Marine Research,
Helsinki
Sea Fisheries Institute zooplankton activities
Piotr Margoński, Sea Fisheries Institute, Gdynia
Chairs: A. Gislason, Iceland, and G. Gorsky, France), adopted
by ICES in 2006, are progressing well. It was decided that the
workshop be held in Heraklion, Crete, Greece in the second
half of October 2008.
During the meeting a ‘Baltic Sea Mini Session ‘ was held during
which scientists from the region presented their research
activities (see text box). A particular focus of these talks was
the importance of introduced species in affecting the community
structure and dynamics of the Baltic. An example cited was the
predatory cladoceran, Cercopagis pengoi (Fig. 2), which was
first found in the Gulf of Riga in 1992. The species is thought to
be of Ponto-Caspian origin having been introduced as a result
of the discharge of ballast water.