Report of the 13th International Scientific Wadden Sea Symposium

Wednesday 21 November

The first day of the symposium started with official welcomes by Jouke van Dijk (chairman of the Waddenacademie), Annemie Burger (Directorate-General for Nature and Regional Affairs of the Dutch Ministry of Economic Affairs), Victor de Jonge (ECSA) and Peter Ilsøe (Wadden Sea Board). In his role of editor-in-chief of the journal Ocean and Coastal Management, Victor de Jonge announced the publication of a special issue on the Wadden Sea and thanked the guest editors Tialda Haartsen and Maria van Leeuwe. Jens Enemark (Common Wadden Sea Secretariat) set the stage for the keynote lectures (see below) by emphasising the outstanding universal value of the Wadden Sea memorising the process of the inscription to the UNESCO World heritage list, the highest international recognition achievable. He also provided a framework for the role of science in safeguarding the values of the Wadden Sea world heritage site.

Starting Wednesday afternoon, the symposium programme was subdivided into four thematic sessions each of which are described below. Each session started off with three selected short presentations on posters that were presented during the poster session on Thursday evening. The full list of posters, including the short presentations can be viewed here.

Thursday 22 November

Session Biodiversity

Day 2 started with a presentation by Prof. Helmut Hillebrand (Institute for Chemistry and Biology of the Marine Environment, Oldenburg-Wilhelmshaven) who applied theoretical concepts, tested by experiments with phytoplankton communities, to the Wadden Sea ecosystem in order to assess the effects of biodiversity change to the functioning of this system.
Dr. Harald Asmus
(AWI Wadden Sea Station Sylt) presented a study on the stability of food webs in the Wadden Sea and the conditions that influence this stability.
The presentation by Prof. Han Olff (University of Groningen) was the first of two talks in which the outcomes were presented of the two-day-workshop on mussels which was held before the start of the ISWSS and organised by "Programma naar een Rijke Waddenzee" and Waddenacademie. Olff discussed the scientific progress on the restoration of ecosystem engineering species in the intertidal. Mussel beds, especially large beds, are important for Wadden Sea biodiversity. In recent experiments it was also demonstrated that they positively influence large parts of the tidal flats.
Marc van Roomen
(SOVON/Wetlands International) stressed the importance of the Wadden Sea Flyway Initiative. He argued that the Wadden Sea should not be studied in isolation. Sometimes changes in the Wadden Sea populations of migrating birds can only be explained by studying the changes that occurred in other areas along the international flyway.

Audience on day 2
Prof. Helmut Hillebrand
Marc van Roomen

The discussion at the end of the session focused on the importance of biodiversity for the ecosystem. There is increasing scientific evidence that a higher biodiversity generally means that the Wadden Sea ecosystem will be more resilient to changes.

Session Science for Management and Policy

After lunch Dr. Esther Turnhout (Wageningen University) immediately grasped the attention of the audience with a critical analysis of the presumed science-policy gap in the Wadden Sea Region. She suggested that it actually might sometimes get a bit too crowded at the interface.
Dr. Rob Steijn (Arcadis) presented the results of a quick scan of the OURCOAST database to identify cases that provide lessons for the management of the Wadden Sea Region. He suggested that the approach used in the UK, with a good representation of local stakeholders in decision-making processes, is worthwhile to analyse in more detail. Possibly elements of this approach could be applied in the management of the Wadden Sea Region.
EBDa.D. Heinz Glindemann, chairman of the advisory board of the TIDE-project gave a presentation on the long term challenges for tidal estuaries using the German estuaries as an example.
Dr. Katja Philippart (NIOZ), head of the WaLTER programme emphasised the importance of an integrated monitoring network and data portal for the Wadden Sea. Using the example of a study on differences between tidal basins of mussel abundance she demonstrated that an improved international data collection will provide more insight into the functioning of the Wadden Sea ecosystem.
Like Prof. Han Olff, Prof. Aad Smaal (IMARES) also provided a synthesis of studies that were presented at the mussel workshop. He discussed the natural dynamics of the mussel beds, fishery impacts and restoration options.

The discussion mostly elaborated on the effectiveness of the science-policy interface in the Wadden Sea Region.

Esther Turnhout
Rob Steijn
Katja Philippart

Poster session

During the lively poster session with over 30 excellent posters, participants voted for the best poster. The poster presented by Piet van den Hout on population dynamics of the bird species red knot won the competition. Several of the voters made reference to the importance of the work that was presented by him and co-authors.

During dinner, Prof. Karsten Reise was honoured by Jens Enemark for his life-long efforts to understand the Wadden Sea ecosystem and for his central role in the preparation of the Wadden Sea world heritage nomination. Prof. Peter Herman (NIOZ) was thanked by Jouke van Dijk for his work as ecologist in the board of the Waddenacademie. Dr. Katja Philippart will be his successor.

Friday 23 November

Session Sustainability and Ecosystem Services

The final thematic session started off with a talk by Dr. Ralf Döring (VTI Hamburg) on fisheries research in the North Sea and Wadden Sea. He showed that the stock size of several fish species such as plaice increased. For some other stocks, e.g. cod, both the fishing mortality and the spawning stock biomass are far from the target of a sustainable fisheries.
Prof. Gilles de Langen (University of Groningen/Province of Fryslân) addressed the term ‘sustainability’ from a cultural-historical perspective. He showed that many of the features of the unique open landscape of the region bordering the Wadden Sea are under threat but there is still a lot to be saved, including the remnants of age-old ditches.
Prof. Victor de Jonge (University of Hull) presented a talk on challenges related to the impact on the ecosystem of harbour development related activities such as dredging and locking off parts of an estuarine system. New models show that it may still be possible to turn the highly turbid Ems system into a more viable ecosystem if appropriate actions are taken without further delay.
Drs. Albert Postma (Stenden University) gave a talk on the possibilities for a sustainable tourism in a world heritage site. He stressed the importance of involving local inhabitants.

While the contributions of this session were diverse, the discussion got a nice focus on the importance of story-telling in the valuation of the Wadden Sea Region.

After the last session the 2012 Wadden Academy award for the best Wadden-related Master's thesis (University level) was handed out to Daniël Postma by Dr. Hessel Speelman. Daniël Postma gave a short overview of the project he is working on: the reconstruction of an old type of clay-wall housing (‘zodenhuis’) which was special to the region. Rindert Dankert had to report that the award for the best Bachelor's thesis (College level) could not be presented because there were not enough submissions.

At the end of the symposium Prof. Jouke van Dijk made a quick synthesis and concluded that the 13th International Wadden Sea Symposium provided us with a good overview of the challenges that we have to meet to maintain the outstanding universal value of this magnificent area. He thanked Tim van Oijen and Sjerpy Joustra for the excellent organisation of the symposium.


In the afternoon bus excursion over 30 participants went into the Northwestern part of Frisia to see the traces the sea has left in the landscape. Excursion leader Prof. Gilles de Langen  showed the successive endikements in the region. At a stop at Zwarte Haan the Wadden Sea could be viewed in a beauty that even locals have rarely viewed it. The second and final stop of the excursion was in the small village of Firdgum, where the participants were welcomed in the museum Yeb Hettinga Skoalle. This museum has an exhibition of archaeological finds of the area. Daniël Postma gave a more detailed explanation of the ‘zodenhuis’ which is being reconstructed right next to the museum. The participants of the excursion got a nice view on the Frisian landscape from the top of the terp of Firdgum at sunset. The day ended with a nice and memorable dinner with our special Korean guests in a great atmosphere.

What’s next?

The coming months the Waddenacademie will synthesise the scientific recommendations made during the symposium. This will be done in close collaboration with the CWSS and the scientific community in Denmark, Germany and the Netherlands. The recommendations of the 13th ISWSS will be taken into account during the preparations for the Trilateral Ministerial Conference early 2014 in Denmark.