The Wadden Sea
constitutes one of the world’s most important wetlands for migratory
waterbirds. It is the single most important staging and moulting area
and an important wintering area for waterbirds on the East Atlantic
Flyway from the Arctic to South Africa. The Joint Monitoring of
Migratory Birds (JMMB) program is carried out in the framework of the
Trilateral Monitoring and Assessment Program (TMAP), and constitutes an
internationally coordinated long-term monitoring program. It covers a
large connected eco-region stretching from Den Helder in The Netherlands
to Esbjerg in Denmark; regular ground counts for most species and areas
plus aerial counts for seaducks involves hundreds of observers and
several institutes and agencies.
After the publication of trends, comprehensive species accounts and
assessments in the most recent reports (Blew et al. 2005 and Blew et al.
2007), the JMMB group agreed, that from now on a yearly update of these
trend calculation shall be published on this website. Here, trends of 34
waterbird species for the international Wadden Sea and the four regions
- The Netherlands, the Federal States of Germany, Niedersachsen and
Schleswig-Holstein, and Denmark will be presented.
Details of the “Joint Monitoring program of Migratory Birds in the
Wadden Sea” are given in Rösner et al., (1993) and updated in Blew et
al., (2005). This program, consisting of international synchronous
counts, spring-tide counts and aerial counts (only Common Eider), has
been carried out by all Wadden Sea countries since 1992. Some
differences between the countries’ programs exist, due to different
national approaches and older already existing counting programs, but
these do not hamper the overall goal for calculating trends. Because
many usable counting data before 1992 exist as well, it has been decided
to include counts back to the season 1987/1988.
The area considered is the Wadden Sea Cooperation Area. This is, in
general terms, the area seaward of the main dike (or, where the main
dike is absent, the spring-high-tide-water line, and in the rivers, the
brackish-water limit) up to 3 nautical miles from the baseline or the
offshore boundaries of the Conservation Area (Essink et al., 2005). The
total area covers 14,700 km², with 4,534 km² of tidal flats.
methods, an overview map of the study area and references for the
Trilateral Monitoring and Assessment Program for migratory birds can be
September 13, 2012
2011. Trends of migratory and wintering waterbirds in the Wadden
www.waddensea-secretariat.org, Wilhelmshaven Germany.