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Non-protected areas
The Skawa River Valley
The Skawa river valley is one of the most picturesque parts of the O¶więcim-Zator Region. In spite of being considerably transformed by man, in many places it has systems close to natural, rich in rare and protected species.
To a considerable extent the Skawa river bed has retained the character of a wild submontane river, changing its features after each major surge. In many places the river cuts into its banks creating vertical cliffs; in other places it deposits the carried material building up gravel bars. Precipitous banks are used by Sand Martins, which nest there in a colony amounting to 600 nests (more information about these birds can be found under the headword: the Soła River Valley).
Willow thickets (so called riverside osiers) develop along the river within the range of average water levels. The thickets consist mainly of shrubby willow species: Salix fragilis the crack willow whose twigs break off easily at the base; Salix purpurea the purple osier, Salix viminalis the common osier and Salix triandra the almond willow whose elastic twigs are used in the wicker industry.
Willow thickets are quite resistant to destructive activity of man, so they have survived in a much better condition than riparian forests and they cover much bigger areas than the latter. Willow thickets do not turn with time into forest communities, as the ice floes floating down the river every year prevent development of woody vegetation.
In the neighbourhood of willow thickets, stretches of riparian forest have survived. Their species composition and spatial arrangement are almost identical to the ones on the Soła River. Another characteristic feature of the Skawa valley is the existence of small water basins situated along the river channel - remains of often uncontrolled gravel extraction. Nowadays they are primarily an angling paradise, but at the same time a biotope for amphibians and birds. Some basins, especially the small ones which are hidden from the public in willow thickets, have become the haunts of beavers. Numerous traces of their activity are easy to spot on the Skawa banks.
In many places near the river, apart from the representatives of the local flora, one can see plants of foreign origin. The most expansive species is Polygonum cuspidatum the Japanese knotweed. The plant comes from Asia, from where it was brought to Europe in the early 19th c. as an ornamental plant. Unfortunately, it has "escaped" from gardens and quickly spread in natural habitats as well. Currently it forms high (up to three metres) compact thickets, seriously threatening the local flora.
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