Wildlife Wednesday - Labor DaY

By Andy Ames

For us humans, Labor Day marks the end of summer - a time to play or cram in as much summer as possible before the cold sets in. In the animal world, rather than a day on the calendar, they rely on the sun. Diminishing daylight tells them that the seasons are changing and it is time to get serious about preparing for season ahead. For some that means taking advantage of the bounty of fruit and seeds. For others it’s time to get down to the business of creating the next generation.

Late summer marks a period of hyperphagia for black bears. This means that essentially they never get full, no matter how much they eat or drink. Bear need to take advantage of every calorie available to put on the fat that will carry them through their winter hibernation. Of course, here in the Estes Valley calorie rich foods are hard to come by. With little hard mast (nuts) and little soft mast (fruits and berries) bear find themselves competing with chipmunks, ground squirrels, and birds for foods such as chokecherries (pictured) wax currants, Oregon grape, and maybe a few of those ground squirrels themselves.

A familiar late August scene in the Estes Valley- elk shedding the velvet from their antlers. This velvety tissue supplied the nutrient to the underlying antlers. By late summer, as hormone levels change, blood supply is cut off and the velvet dries up. Bull elk are often seen rubbing their antlers against trees and other objects to remove the velvet and polish the antlers, all to make them more attractive and imposing for the rut, or mating, season.

Tree squirrels do not hibernate so are busy feasting, building nests, and harvesting cones they store for the winter. If you hear rustling or crashing noises in the woods, look up and you may see a Pine squirrel cutting off and dropping pine cones to the ground.

Marmots do hibernate and have been busy building up fat reserves all summer (busy is a relative term for the placid marmot). At higher elevations they may have already shut down for their long winter nap.

Ground squirrels, too, are fattening up in preparation to hibernate. They primarily feed on fungi and seeds, as well as the occasional carrion. I love watching them reach up and bend over stalks of grass to get to the seeds at the top. Golden-mantled ground squirrels like this one will be active for several more weeks, while most of the Wyoming ground squirrels of the Estes Valley are already hibernating underground.