- Sylvia paludicola Vieillot, 1817
IUCN: VU; Be (II); Bo (I); EUBD (I); RDBUkr: Зникаючі
Value of species
Surveys in 1995-2005 discovered previously unknown populations of this species, resulting in a substantially increased population estimate. However, it probably declined rapidly until the late 1990s, as a result of the destruction of its habitat, at a rate equivalent to 40% in 10 years. It therefore qualifies as Vulnerable. The population is still widely conservation-dependent. The genetically distinct and isolated Pomeranian population is still declining and at a critical level, while the population in Hungary recently declined to extinction, and that in Lithuania continues to decline.
Acrocephalus paludicola breeds across a highly fragmented range at fewer than 50 regular breeding sites in the following countries, with numbers given of singing males between 2002 and 2011: Poland, 2,670-3,850; Belarus, 3,940-6,300; Ukraine, 2,000-4,600; Germany, fewer than 25, and Lithuania, 110-309 (M. Flade and L. Lachmann in litt. 2007, U. Malashevich in litt. 2012). On migration, it has been recorded in c.15 European countries, mainly in the west and southwest of the continent (U. Malashevich in litt. 2012). It winters in the Sahelian belt of sub-Saharan West Africa, mainly along the lower Senegal River, where it was discovered in January 2007 within and to the north of Djoudj National Park (Bargain et al. 2008, Flade 2008, U. Malashevich in litt. 2012), and in 2011 found in smaller wetlands in south-west Mauritania and at the inner Niger Delta in Mali (U. Malashevich in litt. 2012). Two-thirds of the known population has been discovered since 1995, and the total population is estimated at 12,100-14,700 singing males. Since 1970, it is likely to have declined significantly as a result of the destruction of 80-90% of its habitat in the river systems of upper Pripyat, Yaselda (Belarus) and Biebrza/Narew (Poland). These systems hold approximately 75% of the European population. Owing to extensive conservation projects, the decline has been stopped in its central European strongholds in eastern Poland, Belarus and Ukraine, but continues in the Pomeranian population of northwest Poland and northeast Germany. In Hungary, the population collapsed in 2002-2007. The tiny Siberian population is on the brink of extinction and has probably already disappeared, in which case the species has become a European endemic breeder (M. Flade and L. Lachmann in litt. 2007).
The population is estimated at 11,000-16,000 singing males (M. Flade in litt. 2012), equivalent to 22,000-32,000 mature individuals or 33,000-48,000 individuals in total.
Trend Justification: This species probably declined rapidly until the late 1990s, as a result of the destruction of its habitat at a rate equivalent to 40% in ten years. The 2015 European Red List of Birds estimated the European population to be decreasing by 30-49% in 13.2 years (three generations) (BirdLife International 2015).
It breeds in large open lowland marsh habitats with low grassy vegetation (mostly sedge fen mires) with water mostly less than 10 cm deep (Aquatic Warbler Conservation Team 1999). It winters in similar habitats (the grassy saline Scirpus, Eleocharis and Oryza marshes of the Senegal and Niger deltas) and, on migration, favours coastal habitats with low stands of sedge and reed near open water (Flade et al. 2011).