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Non-protected areas
The Soła River Valley
The natural environment of the lower stretch of the Soła River is one of the most interesting and best preserved ecosystems of the Carpathian tributaries of the Vistula. There are riparian forests and non-forest communities with outstanding wildlife and landscape value. Water basins which originated as a result of gravel extraction and shallow oxbow lakes are other characteristic elements of the Soła valley. Riparian forests (riverside broadleaf forests) are particularly notable - they are some of the richest in species and at the same time the rarest forest communities in Europe. Their existence depends on periodic river flooding. Originally, the natural vegetation of the Soła riverside areas consisted of willow-poplar riparian forests. Up to now only their small stretches have survived because of human activity (regulating the river channel, gravel extraction etc.) The areas that have retained most of their natural character astonish with an abundance of dwellers and lushness of vegetation.
The tree cover consists mainly of willow species and black poplar. In the ground cover masses of impressive sized plants develop, e.g. Urtica dioica the stinging nettle, Aegopodium podagraria the ground-elder or Petasites hybridus the common butterbur - a species which has the biggest undivided leaves (100 x 60 cm in diameter). Also creepers develop here in abundance: Humulus lupulus the common hop, whose hops (female flowers) contain lupuline, used during beer brewing; and Solanum dulcamara the bittersweet with intensely red, poisonous berries. One of noteworthy protected species is the ostrich fern. Some of the few locations where this rare plant occurs are situated in the Soła Valley.
The species composition of the avifauna of the Soła and Skawa valleys is almost identical. In the Soła valley around 90 bird species have been noted to occur. Birds from the family Charadriidae breed on the stone beaches: Charadrius dubius the Little Ringed Plover and Actitis hypoleucos the Common Sandpiper. The valleys of both rivers are two of the most important places of occurrence of these species in southern Poland. Their nest is a hole dug in the sand or gravel, where a female lays four eggs amounting to 60% of her body weight. Chicks leave the nest a few hours after hatching and for a couple of weeks stay in their parents care. When threatened, parents pretend to be easy prey, simulating e.g. a broken wing. They trail it helplessly along the ground, in a clumsy attempt to escape. Having drawn away the unwelcome guest to a safe distance from the nest, the adult bird nimbly takes flight and disappears.
Vertical cliffs provide nesting sites for Alcedo atthis European Kingfishers and Riparia riparia Sand Martins. The first species uses its beak and legs to bore a burrow. Building a one-metre tunnel together with a nest chamber takes it about three weeks. Kingfishers line the nest with pellets comprising undigested scales and fish bones. The birds obtain food diving mainly after small fish, which they look out for sitting on tree branches on the river bank. Unlike Kingfishers, Sand Martins nest in colonies. They spend winter in south-eastern Africa. During the passage to the wintering grounds they cover a distance of ten thousand kilometers.
Willow thickets and riparian forests are a habitat where e.g. Luscinia megarhynchos the Common Nightingale and Carpodacus erythrinus the Common Rosefinch occur. The easiest way to recognize these small passerines leading a secretive lifestyle is by their characteristic loud singing. Melodious songs of the Common Nightingale are regareded as some of the most beautiful among bird calls. The loud whistle of the Common Rosefinch sounds like the Polish name of the bird dziwonia. A male Rosefinch is also easily recognizable by its crimson feathers on the head, chest and rump.
Riparian forests are inhabited by yet another interesting species, Remiz pendulinus the European Penduline Tit - a small bird related to Tits. A male of this species builds a very characteristic nest made of fibres and plant down, in the shape of a pendulous bag. It hangs on a twig, usually above water. In the breading season the bird builds a few nests showing them to each of its females to assess.
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