Warta River Mouth (930)
Poland, Europe
Site overview
KBA status: confirmed
Global KBA criteria: D1a
Year of last assessment: 2010
National site name: Ujscie Warty
Central coordinates: Latitude: 52.5667, Longitude: 14.7167
System: freshwater, terrestrial
Elevation (m): 10 to 16
Area of KBA (km2): 333.44816
Protected area coverage (%): 99.59
KBA classification: Global
Legacy site: Yes
Site details
Site description: The site includes the flood-plain of the Warta river, where it meets the Odra river, and the lower course of the Postomia river. There are unregulated stretches of river, oxbow lakes, old drainage channels, small lakes, periodically flooded meadows, and pastures. The area floods almost every year, with annual fluctuations in water-level of up to 3.5 m. Highest levels are in March and April. In some years the whole area is underwater all year, in others for only a few months or not at all. Accordingly, the vegetation varies in different years. During heavy floods water-fringe vegetation predominates, mainly reed Phragmites and especially reed-grass Glyceria and canary-grass Phalaris, occupying a few hundred hectares. Large areas that have recently emerged from water are occupied by ruderal herbs Polygonum/Bidens. When the flood is limited or does not occur, such vegetation dies and is replaced by dry-ground vegetation and willow Salix bushes.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.
Additional biodiversity: A very important area for moulting, staging, wintering and roosting waterbirds, mainly wildfowl. Up to 33,000 duck (Anatidae) stage here during spring migration, with up to 78,000 in autumn. Over 240 species have been recorded, including 160 breeding species. Data in table are for 1991-1996 unless otherwise stated
Habitats
Land use: agriculture (10%) | water management (100%)
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Grassland | 50 | |
| Forest | 4 | |
| Wetlands(Inland) | 3 |
Threats
Summary of threats to biodiversity at KBA: Threats include a lack of water in some years (due to management of water-levels primarily for human uses), overgrazing by domestic geese and cattle, strong expansion of willow Salix scrub (partly due to abandonment of agriculture), disturbance of birds, river dredging, and recreation, tourism and hunting.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Natural system modifications | Dams & water management/use | Large dams | Ongoing |
| Agriculture & aquaculture | Annual & perennial non-timber crops | Agro-industry farming | Ongoing |
| Invasive & other problematic species, genes & diseases | Invasive non-native/alien species/diseases | Unspecified species | Ongoing |
| Climate change & severe weather | Habitat shifting & alteration | Ongoing |