John Shaw / Grey wolf in snow (Canis lupus), Minnesota, USA. January. Controlled situation.

John Shaw / Grey wolves running in snow (Canis lupus), Minnesota, USA. January. Controlled situation.

Danny Green / Black bears (Ursus americanus) three cubs, one climbing, Minnesota, USA, June

Shattil & Rozinski,Shattil & Rozinski / Black bear (Ursus americanus) cub climbing a fence, Minnesota, USA, May.

Lynn M Stone / Trumpeter Swans (Cygnus buccinator) with heads up after dipping to feed in shallow waters. Mississippi River, Minnesota, USA, February.

Visuals Unlimited / White-tailed Deer fawns among ferns in an Aspen forest (Odocoileus virginianus), Minnesota, USA.

Bryan and Cherry Alexander / Ice-fishing huts on Mille Laks Lake. Minnesota, USA, 1985.

Lynn M Stone / Trumpeter Swans (Cygnus buccinator) in winter morning mist, showing aggression during courtship behaviour, Mississippi River, Minnesota, USA, February

Lynn M Stone / Trumpeter Swans (Cygnus buccinator) in winter morning mist, showing aggression during courtship behaviour, Mississippi River, Minnesota, USA, February

Kirkendall-Spring / Two Harbors Hiking Trail / path in Split Rock Lighthouse State Park, Minnesota, USA

Thomas Lazar / American mink, wet after swimming {Mustela vison} Kettle river, Minnesota, USA

Thomas Lazar / Beaver {Castor canadensis} next to felled tree, Kettle River, Minnesota, USA captive

Lynn M Stone / Woodchuck family in grass {Marmota monax} Minnesota, USA

Thomas Lazar / Two Coyotes {Canis latrans} fighting on frozen pond, Kettle River, Minnesota, USA, winter

Lynn M Stone / Grey wolf portrait, Minnesota, USA.

Lynn M Stone / Striped skunk, Minnesota, USA.

Lynn M Stone / Woodchuck holding plant food in paws (Marmota monax) Minnesota, USA

Lynn M Stone / Woodchuck in flower meadow (Marmota monax) Minnesota, USA

Lynn M Stone / Striped skunk (Mephitis mephitis) USA captive

Thomas Lazar / Black bear juvenile sitting in grass, Minnesota, USA.

Thomas Lazar / Black bear cub climbing tree, Minnesota, USA

Jim Brandenburg / Moose (Alces alces andersoni) female looking in car window during winter, the animals lick salt off of cars, Minnesota

Jim Brandenburg / American Beaver (Castor canadensis) with a stick underwater, Minnesota

Jim Brandenburg / White-tailed Deer (Odocoileus virginianus) buck, Minnesota

Matthias Breiter / Black Bear (Ursus americanus) cub in tree safe from danger, Orr, Minnesota

Matthias Breiter / Black Bear (Ursus americanus) juvenile male in tree, Orr, Minnesota

Benjamin Olson / Great Gray Owl (Strix nebulosa), Sax-Zim Bog, Minnesota

Alan Murphy/ BIA / Sharp-tailed Grouse (Tympanuchus phasianellus) males fighting at lek in snow, Minnesota

Alan Murphy/ BIA / Sharp-tailed Grouse (Tympanuchus phasianellus) males fighting at lek in snow, Minnesota

Alan Murphy/ BIA / Sharp-tailed Grouse (Tympanuchus phasianellus) male displaying at lek in snow, Minnesota

Benjamin Olson / Skim ice in negative thirty degree fahrenheit at sunrise, Lake Superior, Grand Portage National Monument, Minnesota

Benjamin Olson / Cave at night during polar vortex, Lake Superior, Tettegouche State Park, Minnesota, multiple exposures

Benjamin Olson / Storm clouds, Lakeville, Minnesota

Jim Brandenburg / American Bison (Bison bison) herd on prairie with quartz, Blue Mounds State Park, Minnesota

Jim Brandenburg / Fishing Spider (Pisauridae) pair on moss, Minnesota

Jim Brandenburg / Forest on lake shore, Judd Lake, Superior National Forest, Minnesota

Jim Brandenburg / Shoreline, Discovery Lake, Boundary Waters Canoe Area Wilderness, Minnesota

Jim Brandenburg / Fire in prairie, Minnesota

Ingo Arndt / Timber Wolf (Canis lupus) running in snow, Minnesota

Ingo Arndt / Timber Wolf (Canis lupus) crossing river, Minnesota

Jim Brandenburg / Thickspike Gayfeather (Liatris pycnostachya) flowering on tallgrass prairie, Crow-Hassan Park Reserve, Minnesota

Jim Brandenburg / Blue Jay (Cyanocitta cristata) pair fighting while a third watches, Minnesota

Jim Brandenburg / Sundogs, also known as mock sun, with snow field, Minnesota

Jim Brandenburg / Thickspike Gayfeather (Liatris pycnostachya) flowers with eagle-shaped cloud, Touch the Sky Northern Tallgrass Prairie National Wildlife Refuge, Minnesota

Konrad Wothe / Timber Wolf (Canis lupus) mother with two pups begging for food at den entrance, Pine County, Minnesota

Jim Brandenburg / Blue Jay (Cyanocitta cristata) perching in pine tree, Minnesota

Jim Brandenburg / Oak (Quercus sp) leaves in stream with snowy forest, Minnesota

Jim Brandenburg / Farm house and tree-lined road in winter, Minnesota