Cosima Tegetmeyer - Institut für Botanik und Landschaftsökologie ...

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Until the end of the 19 th century the Aquatic Warbler (Acrocephalus paludicola) used to be a
common species of the European peatlands. In the 20 th century the population declined
dramatically due to extensive destruction of its wildlife habitat (drainage and intensifica-
tion of agriculture). Today it is globally threatened. Last breeding grounds are found in
Belarus, Germany, Hungary, Latvia, Lithuania, Poland, Russia and Ukraine. The global
population is estimated at around 12,000-20,500 singing males (Aquatic Warbler Conser-
vation Team 2006a). The smallest and most endangered population is the West-
Pommeranian. It is believed to constitute the last part of a huge Western population (over
10,000 individuals) and to be genetically separated from all other known Aquatic Warbler
populations (Giessing 2002). Between 1996 and 2006 it decreased from approx. 250 to 80
singing males.
The present study concentrates on the Aquatic Warbler breeding site “Rozwarowo-mire“
in Poland, a 1600 ha sized peatland that shelters nearly 50 % of the West-Pommeranian
population. In 2006, 37 singing males were counted in the Rozwarowo area.
In the past, the peatland had been used for grazing, mowing and peat production pur-
poses. It had never been drained, despite previous plans to do so (Dreyer 1913). Since
1989 extensive winter reed-cutting has taken place. The Reed (Phragmites australis) consti-
tutes a typical local vegetation widely used for thatches. In 2004, along with the enlarge-
ment of the European Union (EU), the peatland was pronounced a NATURA 2000 site.
Starting from the above facts this study attempts to answer the following questions:
1. Is it possible to combine both economically useful reed-cutting and desirable
Aquatic Warbler protection in the Rozwarowo area?
2. What measures can be taken to pave the way to possible results?
I started to look at the stratigraphy, the abiotic habitat characteristics and the vege-
tation of the central portion of the peatland in July 2005 for the purpose of under-