PROJECT DESCRIPTION
BACKGROUND
The Lake Constance forget-me-not (Myosotis rehsteineri), as its name suggests, is only found along the shores of Lake Constance. Here, in the lake's natural flood plain, it thrives on the gravel banks built up during the postglacial period from pebbles washed down by the Alpine rivers. When lake levels are at their lowest, the forget-me-not blossoms; then many a strip of shoreline is covered with a light blue sheen¿ a sight that has unfortunately become all too rare. One important reason for this decline is because up to the beginning of the 1980s large amounts of gravel for the building industry were extracted from the lake right next to the shore. Consequently, the broad gravel banks which once gently sloped down into the lake's depths gradually disappeared and were replaced by unstable steep shorelines where the motion of the waves rolls the gravel to and fro unimpeded, leaving no chance for the delicate gravel bank flora to take hold. Near the Austrian city of Bregenz, where due to increasing erosion, as described above, the Lake Constance forget-me-not could only be found on a small stretch of shoreline by the end of the 1990s, a technique that had been successfully applied on the German side of the lake would be used within a LIFE project to restore the banks.
OBJECTIVES
The basic principle of the restoration technique used within the LIFE-Nature project is stabilisation of the shoreline. This is done by laying a line of coarse pebbles along the current low-water mark (to absorb the shock of the breaking waves), then filling the space between this line and the original shoreline with a thin layer of finer gravel similar to the shore sediment previously found here. The choice of grain size of the gravel to be used for the outer border and the shallow infill depends on the inclination of the slope and the wave forces to be expected at that point. A total of 2600 metres of shoreline would be treated by this technique. The work would be carried out in winter so as to avoid damaging the sensitive plant life on the shore. When finished, the restoration would only be visible during times of extremely low lake levels.
RESULTS
The prime objective of the LIFE-Nature Project was to restore 2,600 metres of eroding lake shore at Bregenz, in order to guarantee the survival of habitats and species living in the erosion zone and to improve their living conditions. At the same time, the gravel deposited under water would serve as spawning ground for fish. During the project implementation, two new threats to the site turned up: (1) political and social pressure to weaken the protection status of the project site, which is situated on a very attractive lakeshore part within the city limits of Bregenz and (2) recreational pressure on the shoreline, made more attractive after the restoration work, became stronger and so generated a need for optimal visitor guidance. The project tackled both threats successfully by carrying out intensive public relations, communication and visitor guidance work. Actions completed by the LIFE-Nature project: • the technical restoration and renaturation measures for the shoreline were implemented as foreseen, during the low water periods each winter (over four years) • a video film entitled “Grillfest meets Haubentaucher“ (“Barbecue versus great crested grebe“) was produced by six young people, dealing with the many forms of recreation and their impacts on the Natura 2000 area • a stream was restored and nesting places for the kingfisher created, by a youth project • a discussion process about the contents of the project and the regulations for the special protection area, which involved the local population, politicians, external consultants and official representatives, led to longer-term solutions for the area and its users. • UferNatur, a visitor guidance and information programme initiated in late 2000, was expanded considerably. Panels, an educational nature trail, seasonal brochures, information and thematic posters, maps and advertisements informed the visitors and the local population about the protection status and the code of conduct in the protected area. • a homepage designed and maintained by secondary school students provided information on the activities of the LIFE project via the internet. • in addition to the traditional nature guards, voluntary assistants and paid supervisory staff took care of personal visitor information and the implementation of the protected area regulation. • In 2003, the designated Natura 2000 site received its regionally valid protection status. 15.5 ha Annex I habitats within the project area were directly or indirectly affected by the construction measures. These include: • 0.47 ha habitat type 3130: Oligotrophic waters in medio-European and perialpine area with amphibious vegetation: Litorella or Isoëtes or annual vegetation on exposed banks (Nanocyperetalia). • habitat type 3140: Oligo-mesotrophic waters with benthic vegetation of chara. This relates to a nutrient-poor lake section which serves as feeding and breeding habitat for a number of Annex II species in the project site such as Rhodeus and Cottus gobio, as well as the Annex I birds Tringa glareola, Sterna spp. • The project brought indirect benefits for habitats 6410 Molinia meadows on chalk and clay (3.61 ha), 7140 transition mires and quaking bogs (0.05 ha), 7230 alkaline fens (0.23 ha), *91E0 residual alluvial forests Alnion-glutionoso-incanae (1.4 ha) and 91F0 mixed oak-elm-ash forests of great rivers ( a few ha). All of these habitats are only scattered and small but host a number of Annex II species, e.g. Maculinea and Bombina species, as well as Annex I birds like Botaurus stellaris and Alcedo atthis. The benefits for these habitats stemmed from the reduction of trampling and disturbance due to the visitor guidance measures implemented by the project, and from the litter meadow management enshrined in the Natura 2000 site prescriptions which were developed by the LIFE project as well. • Other habitats (not listed in the Habitats Directive) which benefited from the project are reedbeds (9.12 ha; breeding and resting habitats for bird species) and gravelly/sandy shorelines (10.23 ha) which are potential expansion habitats for the delicate lakeshore vegetation, and therefore of eminent importance for the long-term maintenance of Myosotis rehsteineri, the LIFE project's target species. In 2004, approximately 83,000 individuals of the Lake Constance forget-me-not were counted in the project area – evaluated as a stable population which has very good long-term perspectives, due to the restoration of its habitat and the artificial propagation of the plant during the project implementation.