Synaptomys borealis

photo credit: fieldguide.mt.gov

ID

  • Very short tails
  • Lightly grooved incisor
  • Dull brown upper parts, sometimes with an olive wash
  • Bicolored tail (Whitaker)

Distribution

Credit: Smithsonian Institution

Reproduction

  • Breeding season is from May until late August
  • Litter size is between 2 and 8 young, and females are able to produce more than one litter per season (Smithsonian)

Behavior

  • Scarcely captured and don’t respond to baiting (Whitaker)
  • Active on the surface as well as in their burrows when there is no snow cover, though they stay underground more often in the summer, presumably to avoid predators
  • In the winter they build nests beneath the snow using grasses and mosses and sedges (Smithsonian)

Food Habits

  • Sedges and grasses (Smithsonian)

Size/Life Cycle

  • Average Measurements: 110-140 mm (total length), 27-35 g (total weight)

Predators

  • Ravens (Whitaker)

Habitat

  • Highly variable
  • Sphagnum bogs, dense woods (Whitaker)