Key Biodiversity Areas

Marshy Valley of the Narew River (953)
Poland, Europe

Site overview


KBA status: confirmed
Global KBA criteria: A1d
Year of last assessment: 2010
National site name: Bagienna Dolina Narwi
Central coordinates: Latitude: 53.0833, Longitude: 22.8667
System: freshwater, terrestrial
Elevation (m): 107 to 122
Area of KBA (km2): 234.64497
Protected area coverage (%): 98.89
KBA classification: Global
Legacy site: Yes

Site details


Site description: A marshy stretch of the Narew valley, spanning 58 km between Sura¿ town and ¯ó³tki village, and from 300 m to 4 km wide. The valley has a natural character between Sura¿ and Rzêdziny towns and is periodically flooded. The Narew is a braided, meandering river, and creates a system which occupies the whole width of the valley floor in some places. There is a very rich mosaic of plant communities˜mainly beds of reed Phragmites and sedge Carex, alder Alnus forest and riverside scrub of willow Salix.
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: Breeding species of global conservation concern that do not meet IBA criteria: Aythya nyroca (formerly one pair, now extinct here), Gallinago media (6-8 pairs).

Habitats


Land use: agriculture (10%) | hunting | nature conservation and research (78%) | tourism/recreation (5%) | water management (7%)
IUCN HabitatCoverage %Habitat detail
Other1
Artificial - Terrestrial37
Wetlands(Inland)22
Grassland23
Forest17

Threats


Summary of threats to biodiversity at KBA: During 1978-1981 the riverbed between Rêdziny and ¯ó³tki towns (8 km long) was straightened, broadened and deepened, and meanders were cut off. This drastically reduced water-levels in the river channels and adjoining areas, and the area became intensively used for agriculture. However, soils became parched, water was lost from wells in the surrounding area, and the vegetation composition changed. There are efforts to stop further degradation by reconstruction of river riffles in the area of Rêdziny Dam.
Threat level 1Threat level 2Threat level 3Timing
Natural system modificationsFire & fire suppressionIncrease in fire frequency/intensityOnly in the future
Biological resource useGathering terrestrial plantsUnintentional effects (species being assessed is not the target)Ongoing
Agriculture & aquacultureMarine & freshwater aquacultureSubsistence/artisinal aquacultureOngoing
Natural system modificationsDams & water management/useDams (size unknown)Ongoing
Invasive & other problematic species, genes & diseasesInvasive non-native/alien species/diseasesUnspecified speciesOngoing
PollutionDomestic & urban waste waterType Unknown/UnrecordedOngoing
Natural system modificationsOther ecosystem modificationsOngoing