Population research on small rodents (Rodentia) and shrews (Soricidae) in Steinkjer Municipality – Norway; 2018-2021 based on systematic catches with ordinary mouse traps in traplines

The population cycles of small rodents in Steinkjer Municipality, Trøndelag county in Norway have been followed during the years 2018-2021. Population index based on traplines in young forest/clearcut and old natural spruce forest was one time a year (September) for 2018 and 2019 and for 2020-2021 two times a year (May/June and September) investigated mainly for the species: The Bank Vole (Myodes/Clethrionomys glareolus; Grey-Backed Vole (M. rufocanus and Field Vole (Microtus agrestis, but also for other species of small rodents (Rodentia) as the Wood Lemming (Myopus schisticolor) and Lemming (Lemmus lemmus) and different species of Shrews (Soricidae). Here is presented the data for 2018-2021.