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 communitiesmainly beds of reed Phragmites and sedge Carex, alder Alnus forest and riverside scrub of willow Salix.
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).
Pressure/threats to key biodiversity
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.
National Partial International None7,350 ha of IBA covered by National Park (Narwiañski, 7,350 ha).