Figure 1. Locations of sentinel duck flocks at 5 locations in Germany, Switzerland, and Austria. A–C) Sites at Lake Constance: Radolfzell, Germany (A); Bregenz-Thal, Austria (B); and Altenrhein, Switzerland (C). D–E) Additional sentinel stations at Lake Felchow, Brandenburg, Germany (D), and Isle of Koos, Mecklenburg–Western Pomerania, Germany (E). Yellow dots mark the location of sentinel stations. Red dots mark detections of highly pathogenic avian influenza virus (HPAIV) (H5N1) in dead wild birds in 2006, and blue dots in 2007. In 2008, HPAIV (H5N1) was not found in dead wild birds in any of the 3 countries but was found in a live pochard (Aythya ferina) from Switzerland/Lake Sempach (blue dot in Switzerland).