Shattil & Rozinski,Shattil & Rozinski / Mule deer (Odocoileus hemionus), with the Denver skyline and Rocky Mountains in the background, Denver, Colorado, USA, November.

Konstantin Mikhailov / Mule Deer (Odocoileus hemionus columbianus) female running, rear view. Olympic NP, Hurricane Hill, Washington, USA, October 2009.

Floris van Breugel / Dogwood (Cornus nuttallii) in bloom amongst Giant Sequoia trees (Sequoiadendron giganteum) and two Mule deer (Odocoileus hemionus), Sequoia and King's Canyon National Parks, USA. June. Veolia Environn...

Shattil & Rozinski / Mule deer (Odocoileus hemionus) buck, Cherry Creek State Park, Denver, Colorado, USA

Rolf Nussbaumer / Mule deer {Odocoileus hemionus} buck portrait, Grand Teton NP, Wyoming, USA

Bernard Castelein / Male Mule deer portrait (Odocoileus hemionus) Olympic NP, Washington, USA

TOM MANGELSEN / Mule deer (Odocoileus hemionus), female nuzzling young. Montana, USA

Donald M. Jones / Mule Deer (Odocoileus hemionus) buck, western Montana

Jack Dykinga / Black-tail deer (Odocoileus hemionus columbianus) eating improperly disposed garbage along with plastic wrapping. Olympic National Park, Washington, USA, June.

Jack Dykinga / Black-tail deer (Odocoileus hemionus columbianus) eating improperly disposed garbage along with plastic wrapping. Olympic National Park, Washington, USA, June.

Jack Dykinga / Roosevelt elk (Cervus canadensis roosevelti) stag in velvet, Del Norte Redwoods National Park, California, USA. June Completed Review

Phil Savoie / Mule deer (Odocoileus hemionus) in long grass, Madison Mountains, Montana, USA. September.

Jouan Rius / Mule Deer (Odocoileus hemionus) stag Antelope Island State Park, Great Salt Lake, Utah, USA, March.

Jouan Rius / Mule deer (Odocoileus hemonius) doe, Bryce Canyon National Park, Utah, USA, March.

Connor Stefanison / Mule deer (Odocoileus hemionus) buck in snow near Jasper, Jasper National Park, Alberta, Canada. December.

Connor Stefanison / Mule deer (Odocoileus hemionus) buck resting in snow near Jasper, Jasper National Park, Alberta, Canada. December.

Gerrit Vyn / Pronghorn (Antilocapra americana) skeleton caught in a sheep fence. Both antelope, which jump poorly, and deer commonly get there legs caught in livestock fences leading to a slow suffering death. Obs...

Gerrit Vyn / Bald eagle (Haliaeetus leucocephalus) feeding on Mule deer roadkill in winter snow, Okanogan County, Washington, USA

Gerrit Vyn / Bald eagle (Haliaeetus leucocephalus) feeding on Mule deer roadkill in winter snow, Okanogan County, Washington, USA

George Sanker / Mule deer (Odocoileus hemionus) mother with newborn twins. Yellowstone National Park, Wyoming, USA. June.

George Sanker / Mule deer (Odocoileus hemionus) newborn twins following mother, Yellowstone National Park, Wyoming, USA, June.

George Sanker / Mule deer (Odocoileus hemionus) newborn twins following mother, Yellowstone National Park, Wyoming, USA, June.

George Sanker / Mule deer (Odocoileus hemionus) female with newborn fawns. Yellowstone National Park, Wyoming, USA, June.

George Sanker / Mule Deer (Odocoileus hemionus), mother tends to her just-born twin fawns. Yellowstone National Park, Wyoming, USA, June

Bertie Gregory / Columbian black-tailed deer (Odocoileus hemionus columbianus), foraging on seaweed at sunset, Vancouver Island, British Columbia, Canada, July.

Jeff Vanuga / Mule deer (Odocoileus hemionus) bucks fighting during rut. Wyoming, USA, October.

Jeff Vanuga / Mule deer (Odocoileus hemionus) buck during rut. Wyoming, USA, October.

Mary McDonald / Black-tailed mule deer (Odocoileus hemionus) Yellowstone National Park, Wyoming, USA, September.

George Sanker / Mule Deer (Odocoileus hemionus) mother with newborn twins. Yellowstone National Park, Wyoming, USA, June.

Cheryl-Samantha Owen / Blacktail deer (Odocoileus hemionus) near Port Renfrew, Vancouver Island, British Columbia, Canada, July.

Cheryl-Samantha Owen / Black tail deer (Odocoileus hemionus), Knight Inlet, East Coast, Vancouver Island, British Columbia, Canada, July.

Jouan Rius / Mule deer (Odocoileus hemionus) in Yosemite valley, Yosemite National Park, California, USA, December 2012.

Kirkendall-Spring / Mule Deer (Odocoileus hemionus). Arches National Park, Utah, October.

Jack Dykinga / Mule deer (Odocoileus hemionus) in burnt forest, devastation of the 'Wallow Fire' with life returning after seasonal rain, Apache-Sitgreaves National Forest, Arizona, USA 2011

Todd Mintz / Mule deer (Odocoileus hemionus) two females on the Canadian prairies, Saskatchewan, Canada, January

George Sanker / Mule deer (Odocoileus hemionus) male browsing on vegetation in snowstorm, Yellowstone NP, Wyoming, USA, October

George Sanker / Mule deer (Odocoileus hemionus) two does in woodland, Grand Teton NP, Wyoming, USA, October

Todd Mintz / Mule deer (Odocoileus hemionus) portrait, Regina, Saskatchewan, Canada.

Charlie Summers / Large Mule Deer (Odocoileus hemionus) buck in rutting condition - heavy neck and many-pointed antlers. Bosque del Apache, New Mexico, December.

Charlie Summers / Large Mule Deer (Odocoileus hemionus) buck in rutting condition - heavy neck and many-pointed antlers. Bosque del Apache, New Mexico, December.

George Sanker / Two Mule deer (Odocoileus hemionus) interacting, USA, October

B&S Draker / Mule Deer / Black-tailed Deer (Odocoileus hemionus) buck in snow fall. Rocky Mountain National Park, Colorado, USA.

Matthew Maran / Two Blacktail Deer (Odocoileus hemionus columbianus) sparring with locked horns. Ucuelet, Vancouver Island, Canada, September.

Brent Stephenson / Portrait of a Sitka Black-tailed / Mule Deer (Odocoileus hemionus sitkensis) stag / buck with antlers in velvet. Petersburg, Alaska, United States, July.

Diane McAllister / Small herd of Mule deer (Odocoileus hemionus) moving slowly through tall dry grass in a field. Bosque del Apache, New Mexico, USA, February

Diane McAllister / Black-tailed deer (Odocoileus hemionus columbianus), subspecies of the Mule deer. This young buck eating grass pauses to watch the photographer on a trail in Point Reyes National Seashore. California,...

John Cancalosi / Mule deer (Odocoileus hemionus) portrait of doe standing in long grass, South Dakota, USA

Charlie Summers / Mule deer (Odocoileus hemionus) buck in a snowstorm, Montana, USA