by Mike Thompson
Game Range Ramblings
Seeley Swan Pathfinder
March 26, 1998
As you read this, hundreds of grizzly bears are stirring in or around their dens. From Glacier National Park to Lincoln and Seeley Lake, some serious snow excavation is under way in the high country. Yes, grizzly bears are popping out all over.
Just think of the morning breath! We've all tasted the spoils of the bacteria parties that take place in our human mouths overnight, but imagine the carnage that accumulates over a five month period in the mouth of a grizzly bear that scavenged the gut pile from a hunter-killed elk on the way to bed last fall.
I haven't heard form anyone who's actually seen a bear yet this spring, but we can be pretty sure of their imminent awakenings. In a study of grizzly bears in the northern Swan Range, FWP biologists Rick Mace and John Waller documented an average checkout time of April 11, and the motel maids of grizzly country were rattling carts and pounding on doors as early as March 13.
Mace and Waller radioed and followed 30 grizzly bears between Swan Lake and Hungry Horse Reservoir from 1987-1992. Over this time, they documented 78 denning episodes, and reported some very interesting observations.
They found that grizzly bears and human beings may have more than morning breath in common. Male grizzly bears arose earlier than female bears. The average date of emergence for males was April 2, and the earliest recorded exit date (March 13) was also credited to a male. The average exit dates for females was April 15, and females with cubs usually kept the shades drawn until April 21. One female with cubs couldn't face the day until May 12.
Lest the men in our audience infer too much from these gender-specific results, let me hasten to add that neither of the sexes hit the ground running in the spring. All bears remained within 500 meters of their dens for an average of 15 days after emerging, and males tended to spend a day or two longer with their coffee and Pathfinder than females. Mace and Waller reported that bears were quite lethargic and approachable during this period of early awakening. Other researchers have termed this as "walking hibernation," and grizzlies may be particularly vulnerable to disturbance during this time when they are exposed to the world with their senses dulled.
I would hate to be the casual hiker who stumbled upon a grouchy, sleepwalking grizzly bear with morning breath. Fortunately, Mother Nature has held the odds of such chance encounters low. The average elevation of grizzly dens in the northern Swan Range was about 6,000 feet, and most dens were on relatively steep slopes. As reported in other studies, grizzlies prefer remote locations for denning, which explains why bears could be stirring for many days in the backcountry before humans become aware of them. Such denning sites would normally be protected from human entry by deep snowpack in March and April.
Most of the dens in mace and Waller's study were excavated by the bears, and only one known den site was reused by a radioed bear. All of the radioed bears denned every year, and on two occasions sisters denned together during the winter following dispersal as two year olds. No radio-collared bears died during the denning period.
Mace and Waller recommended that hunting seasons for black bears be structured to minimize the potential for mistaken and illegal kills of grizzly bears, especially females. In the Seeley Lake area (Bear Management Units 280 and 290), spring black bear hunting opens on April 15 and closes on May 15, before female grizzlies have much time to move out of the deep snow country and begin making themselves visible to the average hunter. During that time period, however, male black bears are out and about for hunters to stalk on lower, snow-free slopes. Like grizzlies, female black bears emerge from their dens and become active at a later date than males, so they benefit from this conservative hunting season as well.
The arrival of spring is not signaled only by the arrival of meadowlarks, which, by the way, are now "singing their guts out," according to Bill Thomas. In wilder places at higher elevations, spring is heralded by the abrupt exposure of "gopher" holes you could hide a truck in, and the emergence of big, hairy, rendering plants that you wouldn't want at your bird feeder. Don't go there.