Originally, the occurrence of the garden dormouse stretched from the Atlantic coast of Portugal and France to the Southern Urals in Russia as well as Finland to southern Spain and Sicily. In central, northern and eastern Europe a significant decline is obvious and some regional extinctions had to be recorded, for example
1900 garden dormice in the northern Upper Lusatia (Saxony) disappeared
1925 the last known garden dormouse in the Zittau Mountains (Saxony) was killed by a cat
1959 the garden dormouse is considered as extinct in Lithuania
1973 last sighting of a garden dormouse in Belarus
1988 last sighting of a garden dormouse in Romania
1988 garden dormice in the West Ore Mountains (Saxony) no longer detectable
1991 last sighting of a garden dormouse in Finland
2007 garden dormice in the Bohemian and Saxon Switzerland (Czech Republic and Saxony) no longer detectable
A current Europe-wide analysis by Sandro Bertolino (2017) concludes: “The garden dormouse suffered a significant contraction in its geographical range in the last few decades. The species has disappeared from large parts of central and eastern Europe. Originally it was common in 26 European countries. In 2015, the garden dormouse occupied 49% of its 1978 geographical range and 67% of its 2008 range. It must therefore be considered to be one of the European mammals that suffered the largest decline in recent times”.
The garden dormouse is a “species of responsibility”
A large part of the global garden dormouse range now occurs in Germany. That is why, Germany has a special responsibility to protect this dormouse. According to The National Strategy on Biological Diversity, the aim is reaching sustainable populations by 2020 for species in the Conservation Responsibility for Germany.
Despite this particular responsibility for the conservation of the species, however, there is hardly any up-to-date data on the garden dormouse distribution and its densities in the federal States, with a few exceptions. However, declines are reported from many regions. In the German Red List, the garden dormouse is listed as “endangered to an unknown degree.”
Root cause research
There is no explanation for the rapid decline in the species. The reasons for this disappearance are is still completely unclear. Especially since the decline is a process that began 150 years ago, as Sven Büchner documented it for Saxony.
- Climatic changes
- Changes in habitats
- Changes in food resources
- Influences of food competitors or predators
- Genetic impoverishment
- Diseases or parasites