Bolgenach

Mountain streams, rivers and lakes

The streams, rivers, ponds and lakes in the Upper Allgäu are ecologically extremely valuable habitats with a diverse flora and fauna

 

Flowing waters shape the landscape

Streams and rivers are among the most important landscape shapers in the Oberallgäu. Due to the steep relief (high mountains, deep valleys) they have a steep gradient. The power inherent in them is correspondingly great. They have high flow velocities and form themselves themselves, their banks and the surrounding landscape over and over again. The stream and river courses in the Upper Allgäu change the most during a flood event. Then the water rushing downstream also carries away large boulders and pebbles and changes the beds of the watercourses. Over the millennia, the streams and rivers have thus cut deeply into the landscape in many places and formed mighty gorges and ravines. The flowing waters in the Oberallgäu are therefore extremely dynamic habitats that are subject to constant change - and require a correspondingly high level of adaptability from their animal and plant inhabitants.

 

A life with the flow

The streams and rivers of the Upper Allgaeu are cold, clear, strongly flowing and always saturated with oxygen. They can almost exclusively be assigned to the salmonid region, i.e. they are dominated by salmon-like fish such as brown trout (Salmo trutta forma fario) and grayling (Thymallus thymallus). These species, with their spindle-shaped bodies, are excellently adapted to the high flow velocities. The numerous small creatures in the mountain stream habitat live in constant danger of being carried away by the current. Over time, they have therefore developed numerous adaptations and behaviors that enable them to survive in fast-flowing water. They tend to stay on the underside of rocks, between plant pads, or in the gap space between boulders. In these locations, the flow velocity of the water is much lower. Flattened bodies and the formation of adhesive organs also help them survive in fast-flowing water.

 

Want to cool down?

The Oberallgäu is peppered with clear lakes. Many locals and tourists dive into the cool blue in summer to refresh themselves. However, in addition to being an attraction for people, the Oberallgäu lakes offer an optimal habitat for a wide variety of animal species. Catfish, pike, crayfish, but also water birds can be found here. Due to the optimal water quality in the Oberallgäu, the animal inhabitants feel very much at home.