Image of a hibernating thirteen-lined ground squirrel from University of Minnesota Duluth researcher Matthew Andrews.
Thirteen-lined ground squirrels (Ictidomys tridecemlineatus) are really cute when they hibernate (above). During torpor bouts, their body temperature decreases to a few degrees Celsius and their metabolism drops by as much as 95% with heart rates ranging from only 3-10 beats per minute. These bouts of torpor are interrupted by periodic arousals every couple of weeks during which their metabolism increases as body temperature elevates to 37 degrees…