Hibernation sites of riparian ground beetles (Coleoptera, Carabidae) in Central and Northern Norway

In an attempt to detect the winter quarters of Scandinavian riparian carabid beetles, sites at various distances from some rivers and a lake in Central and Northern Norway were investigated with various sampling methods in early spring (April–primo May), in autumn (ultimo September–November) and during the summer (ultimo May–August). Bembidion bipunctatum (L., 1761) and species confined to gravelly/stony habitats (Bembidion prasinum (Duftschmid, 1812), B. hyperboraeorum (Munster, 1923), B. virens Gyllenhal, 1827, B. hastii (Sahlberg, 1826), B. petrosum (Gebler, 1833), B. saxatile Gyllenhal, 1827 and larvae of B. mckinleyi (Fall, 1926)) hibernate among gravel or under stones (often in grass tussocks) in the most elevated parts of the river banks. Some of these species cluster strongly under stones. Species of fine-grained substratum may hibernate in silty sites in elevated parts of open river banks (e.g. B. difficile (Motschulsky, 1844) and larvae as well as adults of Cicindela maritima Dejean in Latreille & Dejean, 1822), or close to or in fluvial forest (e.g. Bembidion schuppelii Dejean, 1831, B. semipunctatum Donovan, 1806 and Agonum micans (Nicolai, 1822)). The winter quarters of the subgenus Bracteon Bedel, 1879 is still undetected. There is no evidence that riparian beetles migrate far from river banks or lake shores by flight to hibernate. Many riparian beetles are red-listed. Threats to their habitats with special emphasis on their winter quarters are discussed.