Donald M. Jones / Rocky Mountain Elk (Cervus canadensis nelsoni) bull bugling, North America

Donald M. Jones / Rocky Mountain Elk (Cervus canadensis nelsoni) bull running, North America

Donald M. Jones / Rocky Mountain Elk (Cervus canadensis nelsoni) bull crossing road near truck, North America

Eric Baccega / Two Elk (Cervus canadensis) bulls at sunset, Jasper National Park, Rocky Mountains, Alberta, Canada, September

Shattil & Rozinski / Elk (Cervus canadensis) herd grazing, Horseshoe Park, Rocky Mountain NP, Colorado, USA

Donald M. Jones / American Elk (Cervus elaphus nelsoni) bull in velvet with Canadian Rockies backdrop, western Alberta, Canada

Rolf Nussbaumer / Elk / Wapiti {Cervus canadensis} bull bugling beside cow amongst aspen trees, Rocky Mountain National Park, Colorado, USA, September 2006

Tim Fitzharris / Stand of conifers in the Elk Mountains near Crested Butte, Colorado

Lynn M Stone / Elk deer {Cervus elaphus} stag in snow, Jasper NP, Canada

Tim Fitzharris / Elk (Cervus elaphus) bulls, Rocky Mountain National Park, Colorado

Sebastian Kennerknecht / American Elk (Cervus elaphus nelsoni) bull grazing in winter, Gardiner, Yellowstone National Park, Montana

Dawn Y. Wilson / Elk (Cervus elaphus) bull bugling in winter, Rocky Mountain National Park, Colorado