Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) a semi-aquatic rodent swimming across calm pond behind beaver dam on mountain river, fall foliage reflectd in water, evening, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) young animal munching on alder branches in glacial kettle pond, Denali National Park and Preserve, Alaska

Gerry Ellis / Taiga vegetation and pond, Chugach National Forest, Alaska

Michael Quinton / American Beaver (Castor canadensis) slapping water with tail in boreal pond, Alaska

Michael Quinton / American Beaver (Castor canadensis) nibbling on leaf from willow branch in boreal pond, Alaska

Tim Fitzharris / Avery Peak reflected in beaver pond, San Juan Mountains, Colorado

George Sanker / Beaver Pond with mountains and trees reflected in surface, Grand Teton National Park, Wyoming, USA, September 2006

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) swimming in pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) sliding on muddy bank from top of lodge into pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) hauling cut branch to pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) swimming with large cut log, Denali National Park, Alaska

George Sanker / Beaver pond with mountains reflected at dawn, Grand Teton National Park, Wyoming, USA, May 2006

George Sanker / Beaver pond with mountains reflected in water, Grand Teton National Park, Wyoming, USA, May 2007

George Sanker / Beaver pond with an old lodge, Grand Teton National Park, Wyoming, USA, September 2006

George Sanker / Eastern painted turtle {Chrysemys picta picta) on the bank of a beaver pond, Walpole, New Hampshire, New England, USA, Spring

George Sanker / Great blue heron (Ardea herodias) in beaver pond, Grand Teton National Park, Wyoming, USA, June 2008

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) a semi-aquatic rodent swimming branches across calm pond behind beaver dam, fall evening, Denali National Park, Alaska

Tim Fitzharris / Beaver pond amid boreal forest, Tombstone Territorial Park, Yukon Territory, Canada

Thomas Lazar / American beaver on frozen cattail pond (Castor canadensis) Kettle River, USA

Tim Fitzharris / Beaver dam and pond surrounded by boreal forest with Mount Robson in background Mount Robson Provincial Park, British Columbia, Canada

Tim Fitzharris / Haystack Mountain reflected in beaver pond, Maroon Bells, Snowmass Wilderness, Colorado

Philippe Clement / American Beaver's lodge (Castor canadensis) in pond in tundra habitat, Denali NP, Alaska, USA.

JEFF FOOTT / Beaver (Castor canadensis) lodge, dam and pond, USA

Flip de Nooyer / European Beaver (Castor fiber) lodge, Europe

Gerry Ellis / Spruce and deciduous trees advancing into former Beaver pond, display of wetlands succession, Algonquin Provincial Park, Ontario, Canada

Gerry Ellis / Grasses and lilies in beaver pond, Chugach National Forest, Alaska

Gerry Ellis / American Beaver (Castor canadensis) pond with water lilies and forest, Chugach National Forest, Alaska

Michael Quinton / American Beaver (Castor canadensis) chewing on aspen branch in boreal pond, Alaska

Michael Quinton / American Beaver (Castor canadensis) parent and kit gnawing on log in boreal pond, Alaska

Michael Quinton / American Beaver (Castor canadensis) chewing bark off of stick in boreal pond, Alaska

Niall Benvie / Euroasian beaver {Castor fiber} dam. Nr Talsi Latvia Note scum on water behind & clear below

Tim Fitzharris / Boulder Mountains reflected in beaver pond, Idaho

Tim Fitzharris / Avery Peak reflected in beaver pond, San Juan Mountains, Colorado

Tim Fitzharris / Handies Peak reflected in beaver pond, Maroon Bells-Snowmass Wilderness Area, Colorado

Sumio Harada / American Beaver (Castor canadensis) swimming in pond, Glacier National Park, Montana

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) dragging cut branch to pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) swimming in pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) dragging cut branch to pond, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) swimming in pond, dragging branch, Denali National Park, Alaska

Pete Oxford / American Beaver (Castor canadensis) pond with dam and lodge, Grand Teton National Park, Wyoming

Pete Oxford / American Beaver (Castor canadensis) pond with dam and lodge, Grand Teton National Park, Wyoming

Pete Oxford / American Beaver (Castor canadensis) pond with dam and lodge, Grand Teton National Park, Wyoming

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) ponds created by the rodents building dams and raising levels of existing glacial kettle ponds, in colorful autumn tundra, Denali National Park, Alaska

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) a semi-aquatic rodent swimming across tundra pond behind beaver dam, with colorful reflections of fall tundra and vegetation on water ripples created by its passage...

Yva Momatiuk & John Eastcott / American Beaver (Castor canadensis) juvenile swimming in tundra pond behind beaver dam, surrounded by brilliant reflections of fall trees and grasses, evening, Denali National Park, Alaska