COEUR d'ALENE - A mischievous squirrel was responsible for a Monday morning power outage in Coeur d'Alene, according to Avista Utilities.

About 8 a.m., the critter climbed onto electrical lines that cross Interstate 90 along Government Way.

"Somehow the squirrel was in the lines, and caused them to slap together, causing the outage," said Debbie Simock, Avista communications manager.

Sensing the slap, the power system anticipated a problem and shut down, Simock explained. For 30 minutes, 3,388 Avista customers were without electricity.

Crews quickly identified the issue and restored power.

The affected area stretched from Appleway Avenue to the shoreline of Lake Coeur d'Alene, east of Tubbs Hill. The eastern boundary was 15th Street; the western edge was Seventh Street.

Customers in The Coeur d'Alene Resort area were not affected, Simock said, though much of the city was without power.

"This time of year, a lot of the outages we see are caused by animals," she added. "Squirrels, as well as birds that get into substations."

To combat the meddlesome wildlife, Avista has installed rubber boots or plastic cones on many of its insulators - the energized protrusions atop distribution transformers. The boots and cones protect the insulators, preventing squirrels or other animals from touching them, Simock wrote in an email.

Contact with an insulator may cause a power outage and will likely kill the animal.

Unfortunately, squirrels like the warmth of electric transformers, especially on cool mornings, and will often eat or rest on them, Simock wrote.

"In spite of the wildlife guards, squirrels and birds still come into contact with power lines and cause outages. That was the case (Monday) morning."

But Avista's guard program has been effective. Five years ago, squirrels were involved in 902 power outages. By 2010, the number of squirrel-related outages had fallen to 390.