Large biodiversity losses
For the first time, the Federal Office for the Environment has compiled a Red List of four families of native wood-inhabiting beetle species in Switzerland. It makes one sit up and take notice: Almost half of these beetle species are endangered. At the same time, the revised Red List of flowering plants, ferns, clubmosses and horsetails shows that these plants are not faring much better: almost a third of these vascular plant species are endangered. Since their last evaluation in 2002, their status has even worsened.
The extent to which native species are under pressure from habitat changes is illustrated by the newly published Red List of Wood-Dwelling Beetle Species in Switzerland published by the Federal Office for the Environment (Bafu). The findings are alarming: around 46% of the 256 beetle species studied are endangered - i.e. they could become extinct - and a further 18% are potentially so. Compared to the average of endangered species of all animals and plants studied so far (36%), wood-inhabiting beetles are significantly more threatened.
The Red List of Vascular Plants, revised at the same time, also makes one sit up and take notice: 28% of the approximately 2700 native plant species, which include flowering plants, ferns, clubmosses and horsetails, are endangered, 16% potentially so. Compared with the last assessment in 2002, the deterioration has been slowed somewhat for only one-third of the species then at risk, while over 200 species are in worse condition today. This sobering assessment shows that the conservation and promotion of native species requires continued and increased attention.
Species need enough habitats with quality
Each species needs suitable habitats, which, however, are impaired in their quality or lost due to human activities. The four families of jewel beetles, longhorn beetles, rose beetles and stag beetles prefer habitats that have become rare in Switzerland: Floodplain forests, old and dead wood stands, sparse forests, shrub-rich forest edges and hedgerows. As recyclers and decomposers of wood, they are indispensable for the balance of the forest ecosystem. Many of these endangered beetle species depend on very old trees, which are becoming increasingly rare to find. Therefore, it is important to leave old trees as habitats for such animals until they decay, if possible, to maintain them instead of cutting them down where necessary, and to provide for their replacement in good time.
The decline in species of vascular plants mainly affects plant species near and in water, in dry meadows, shrubs and hedges, and in fields and vineyards. Settlement areas and cultivated land are particularly affected: where soils are oversaturated with nitrogen, demanding species are displaced.
Promotion of biodiversity
Some of the native beetle species studied are extremely sensitive to environmental changes. Like vascular plants, they are therefore good indicators of the state of biodiversity. Based on Red Lists and inventories of other species, the federal government and cantons are already implementing biodiversity-promoting measures in the forest and in agriculture, but these must be further strengthened. In concrete terms, this means that habitats should be enhanced, old trees should be preserved as long as possible, forest reserves, old-growth islands and stepped forest edges should be created, and tree care should be carried out with care. Nitrogen inputs are to be reduced.
Since 2012, the Federal Council has been aiming to counteract biodiversity loss with its Swiss Biodiversity Strategy and the associated action plan, which is currently being prepared. Successful implementation of the strategy requires broad-based cooperation between all stakeholders.
Source: Federal Office for the Environment
