Ismaele Tortella / Four Eurasian elk (Alces alces) walking through vegetation , Norway, August

Donald M. Jones / Elk (Cervus elaphus) bull bugling, Alberta, Canada

Paul Williams / Moose (Alces alces) female with twin calves, Baxter State Park, Maine, USA, June.

Daniel J. Cox / Gray Wolf (Canis lupus) predating female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 4 of 4

Daniel J. Cox / Gray Wolf (Canis lupus) killing female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 3 of 4

Daniel J. Cox / Gray Wolf (Canis lupus) attacking female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 2 of 4

Daniel J. Cox / Gray Wolf (Canis lupus) pair predating female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 1 of 4

Jack Dykinga / Roosevelt elk (Cervus canadensis roosevelti) in a meadow beneath redwood trees, Del Norte Redwoods National Park, California, USA. June

Jack Dykinga / Roosevelt elk (Cervus canadensis roosevelti) in a meadow beneath redwood trees, Del Norte Redwoods National Park, California, USA. June

Mark Raycroft / Elk (Cervus elaphus) bull in river in mist, North America

Mark Raycroft / Elk (Cervus elaphus) bulls fighting, North America

Donald M. Jones / Elk (Cervus elaphus) bulls fighting, western Canada