The avifauna of the Lower Noteć River Valley – current state and changes in numbers

Przemysław Wylegała, Andrzej Batycki, Adam Kasprzak

Ornis Polonica 2012, 53: 39–49

https://doi.org/10.12657/ornis.2012.1.2

Abstract: In 2011, selected bird species were censused in the Lower Noteć River Valley between Drezdenko and Santok (an Important Bird Area within the Natura 2000 network). The Lower Noteć River Valley constitutes an important refugee for several waterbird species at a national scale: Greylag Goose Anser anser (81–90 pairs), Garganey Anas querquedula (40–45), Spotted Crake Porzana porzana (83–90), Corncrake Crex crex (111–120), Water Rail Rallus aquaticus (80–90), Common Crane Grus grus (52–55), Common Snipe Gallinago gallinago (260–270) and Bluethroat Luscinia svecica (98–110). The valley’s importance for migrants and wintering birds (e.g. Whooper Swan Cygnus cygnus – 1,250 inds, Northern Pintail A. acuta – 1,500, Eurasian Wigeon A. penelope – 2,500, Eurasian Teal A. crecca – 1,300, Garganey – 300, Northern Shoveler A. clypeata – 600, Bean Goose A. fabalis and Greater White-fronted Goose A. albifrons – up to 9,500) is also remarkable. Among 46 wetland bird species, 18 increased, 19 declined, while remaining 9 were stable in numbers compared to 1981–1982. Observed trends are mostly caused by the environmental changes like disappearance of oxbows, overgrowing of a floodplain terrace by willows, the abandonment of farming intensity and locally appearing secondary wetlands. The biggest decline was found in birds inhabiting periodically flooded meadows (Anseriformes and Charadriiformes) and in species requiring open water surface (grebes, Aythya ducks, Eurasian Coot Fulica atra and Black-headed Gull Chroicocephalus ridibundus). Increases were mostly noted in species which increase in numbers in the whole Poland. Strong increases of Corncrake, Spotted Crake and Bluethroat noted are probably not mirroring their national trends.

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