Carabus nodulosus is a highly localised habitat directive species which occurs along forested mountain streams, at an altitude between 400 and 800 metres above sea-level. In France it is only found in a small part of Les Vosges and in Germany it has also a very limited distribution. The species also occurs in Slovenia, Austria and a very small area in East Hungaria, but also only in scattered small populations. Sustainable populations are found where the humid alluvial zone, along small and slowly flowing forest streams, is broad enough. It is an extremely hygrophilous species, which often hunts under water and along the shores of stony small forest streams and brooks. It is a stenotopic forest species, with a very low dispersion capacity. As a lot of the small forest streams at the mentioned altitude often have rapid flowing courses in a narrow gorge, the amount of suitable habitat along a small forest stream is often limited. Once suitable habitat is found, the species is not uncommon and can even be quite abundant. The problem is that the suitable habitat often only consists of an area of a few hundreds of meters along the stream and is often only a few tens of meters wide. These small patches of suitable habitat are often separated from each other by some kilometers of unsuitable habitat. German research has shown that these populations often consist of 50 to 300 individuals. As the species has a very low dispersion capacity these populations have often no contact with other populations along the same river or other small rivers in the same forest area. The only exception to this can happen after heavy rainfall, when specimens get washed away by the stream and wash ashore in a lower part. The relative strong isolation of most of the populations, make the species very vulnerable for forest exploitation. As the species is stenotopic, it can suffer severely from intense forest activities and clearcuts along their habitat. Once struck by this, it is very difficult for the species to recover as the numbers have then declined to a critical amount. It is then often unlikely that the losses can be soon enough compensated by new colonisations from other viable populations. All these characteristics have made the Carabus nodulosus a localised and elusive species within its natural distribution. In Belgium, Switzerland and Italy the species is listed as 'extinct'.