Abstract:
Burrowing mammals often have considerable geomorphological impacts, and their
tunneling activities may decrease the stability of landforms. We document the spatial
distribution of Norwegian lemming burrows in a subarctic alpine meadow to
determine the preferred locations for burrow entrances and to examine the potential
for burrowing to decrease the stability of periglacial landforms at the site. Burrow
entrances were disproportionately common into the base and sides of landforms
(.68% of burrows), probably reflecting the lower energetic cost of moving soil
horizontally, rather than vertically, out of burrows. Most burrow entrances (.60%)
were also located under large rocks, which probably improve burrow stability by
providing a firm ceiling to the entrance. Field observations show that these burrows
are relatively stable, as only 3% were associated with any signs of increased erosion
or landform instability. Therefore, in contrast to some previous studies, and despite
burrowing being concentrated on landforms, we suggest that these rodents have little
direct impact on landform integrity at this site.