March 25, 2015

Where the Wild Things Sleep – Grizzly Bear Den Sites Revealed Thanks to GPS Technology

Banff's first grizzly bear was spotted last week, by hidden camera.  Bear #122, a large male that has made his home in the Bow Valley for the last few years, was captured by one of the park's automated cameras at a research site near Castle Junction on March 19.  Adult male bears are often active by March. The rest of the gang (subadults, lone females, moms with cubs) will come out of hibernation over the next six or eight weeks.

Out of sight usually means out of mind, but we often wonder where bears are spending the winter.  We don't know where they are, but we have a friend who does.  Brian Spreadbury works for Parks Canada in their Resource Conservation department, and specializes in wildlife work.  He can use GPS data to find bear den sites.  Since 2012, a handful of Banff's grizzly bears have been fitted with GPS collars, allowing researchers to track their movement.  Every fall, when the GPS signal suddenly disappears, you know that a bear has gone into its den.

Using the last transmission point as a guide, Brian has discovered several dens.  If you're wondering, he waits until the summer or early fall, long after the bear in question has emerged, so he doesn't disturb them.  Last fall, Brian sent us a photo of the den used by grizzly bear #72, a local female, in the winter of 2103 – 2014.  The park likes to keep the exact location of dens a secret, but Brian recorded all the other info about the den.  Take a look, and imagine yourself spending six months snoozing in this particular spot...