The U.S. has an aging power grid that is vulnerable to attack, according to a recent Associated Press investigation. Our extreme dependence on this relatively defenseless network is so much of a threat that even Pentagon officials are worried. As serious as these concerns are, there's another enemy that unintentionally attacks the U.S. power infrastructure on a regular basis: squirrels.

The furry, fluffy-tailed rodents hop and scramble through their environment, often encountering the lines, poles and transformers that people rely on for electricity, John Metcalfe reports for The Atlantic. With one misstep or bite to the line—ZAP! The unlucky animal dies along with an entire neighborhood's electricity.

Despite the potential jokes, the scope of this menace is quite serious. An East Coast resident under the pen name CyberSquirrel has mapped the path of destruction by squirrels and their wildlife compatriots by combing through news reports.

This also isn't a new problem for power companies. The American Public Power Association actually tracks outages on a "squirrel index," writes Katherine Shaver for The Washington Post. Storms cause longer and larger outages, but squirrels are responsible for the greatest number of power outages, she reports.

CyberSquirrel tells Metcalfe that they've logged 300 events in 2015 worldwide, but the true count of such incidences is likely much higher: Squirrels caused 560 power outages in the state of Montana in 2015, reports Kate Whittle for the Missoula Independent. The map only has pins for three of those incidences.

The map's count may soon improve. "We have some friends in a few small power companies that have sent us their historical and/or current animal outage data," CyberSquirrel tells The Atlantic, "and it is taking us a bit of time to integrate that into our data."

The map's tongue-in-cheek tone certainly draws attention (the events are referred to as "successful cyber war ops"), but the prevalence of these events is a sign that something must be done. Utility companies are starting to install squirrel guards such as slippery materials around power poles, Shaver reports for The Washington Post.

Clay C. Perry, spokesperson for the Palo Alto, Calif.-based Electric Power Research Institute tells Shaver, "we’ve looked at this fairly extensively, because as cute and little as they are, they can cause major damage."