According to a report filed by Northwestern Energy, of the thousands of power outages in Montana last year, a substantial amount were caused by woodland creatures.

"In the Northwestern service territory in 2012, there were 6,643 outage incidences," said Montana Public Service Commission Chief Legal Council Justin Kraske. The peak months look like April and July and they're actually broken down further on the graphs as to what kind of outage it is."

The break down shows some surprising things, like, for instance, that squirrels caused more outages than either lightning, ice or tree limbs. Following are the major causes of power outages ranked by number of incidents in 2012.

  1. equipment failure
  2. unknown cause
  3. wind
  4. tree in line
  5. squirrel
  6. lightning
  7. birds
  8. snow and ice
  9. scheduled maintenance
  10. tree limb in line

For those interested, the report also details which months saw a prominence of different types of outages. Apparently, April and May are peak months for power outages caused by squirrels.

Justin Kraske: