Distribution of small mammals among successional and mature forest types in western Labrador

Abstract

The effects of secondary succession following forest fire on vegetation structure and small mammal populations were » determined on ten sites near Labrador City (Newfoundland, Canada).Study plots represented six successional stages and one fen.The abundance of small mammals on plots increased with the succcessional age of the plot.The Boreal Red-) backed Vole, Clethrionomys gapperi was the most common small mammal species while the Meadow Vole, Microtus | pennsylvanicus, the Heather Vole, Phenacomys intermedius, and the Masked Shrew, Sorex cinereus, were restricted in distribution.C. gapperi was positively associated with trees > 2 m high and broad leafed shrubs 0.5 m high while negatively associated with lichens.M. pennsylvanicus was positively associated with grasses/sedges and negatively associated with trees < 2 m high.P. intermedius was positively associated with downed woody debris.S. cinereus was negatively associated with grasses/sedges and positively associated with broadleafed shrubs <0.5 m high.Some correlations among the abundances of small mammals and habitat variables may not reflect cause and effect relationships: C. gapperi's negative association with lichen and S. cinereus's negative association with grasses/sedges.