Tim Fitzharris / Surf crashing on rocks at Keoneloa Bay, Kauai, Hawaii

Tim Fitzharris / Waterfall along Hana coast, Maui, Hawaii

Tim Fitzharris / Paradise River cascade, Mt Rainier National Park, Washington

Tim Fitzharris / Paradise River surrounded by spring flowers, Mt Rainier National Park, Washington

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) harem stallions posturing as prelude to fight, Montana

Tim Fitzharris / Paradise River, Mt Rainier National Park, Washington

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) family band running together in desert, Fifteen Mile Herd Management Area, central Wyoming

Tim Fitzharris / Roaring fork river, Great Smoky Mountains National Park, Tennessee

Tim Fitzharris / Multnomah Falls cascading through temperate rainforest, Columbia River Gorge near Portland, Oregon

Tim Fitzharris / Startrails over Shiprock in four corners region, New Mexico

Jim Brandenburg / Cascading stream, Great Smoky Mountains National Park, North Carolina

Flip Nicklin / Bottlenose Dolphin (Tursiops truncatus) pair, Waikoloa Hyatt, Hawaii

Tim Fitzharris / Rufous Hummingbird (Selasphorus rufus) feeding on the nectar of a Desert Figwort (Scrophularia desertorum), New Mexico

Jim Brandenburg / Ice next to creek, Minnesota

Jim Brandenburg / Ice next to creek, Minnesota

Tim Fitzharris / Broad-tailed Hummingbird (Selasphorus platycercus) feeding on the nectar of a Desert Penstemon (Penstemon pseudospectabilis) flower, New Mexico

Jim Brandenburg / Honeymoon Falls at summer solstice, Judd Creek, Northwoods, Minnesota

Jim Brandenburg / Kawishiwi Falls, Kawishiwi River, Boundary Waters Canoe Area Wilderness, near Ely, Minnesota

Ingo Arndt / Semipalmated Sandpiper (Calidris pusilla) and Red Knot (Calidris canutus) flock, Delaware Bay, Delaware

Ingo Arndt / Semipalmated Sandpiper (Calidris pusilla) and Red Knot (Calidris canutus) flock, Delaware Bay, Delaware

Konrad Wothe / Reflections in Sol Duc River, Olympic National Park, Washington

Tim Fitzharris / Lone Beach at sunset, Oregon

Tim Fitzharris / Little Pigeon River, Great Smoky Mountains National Park, Tennessee

Tim Fitzharris / River in Pedernales Falls State Park, Texas

Tim Fitzharris / River in Pedernales Falls State Park, Texas

Tim Fitzharris / River in Pedernales Falls State Park, Texas

Matthias Breiter / Siberian Tiger (Panthera tigris altaica) running, captive, Kalispell, Montana

Michael Durham / Columbia Sharp-tailed Grouse (Tympanuchus phasianellus columbianus) erupting into flight from tallgrass, Zumwalt Prairie Preserve, northeast Oregon

Michael Durham / Coyote (Canis latrans) running with dead Lamb prey in its mouth, Montana

Tom Vezo / Yellow-billed Cuckoo (Coccyzus americanus) displaying, Rio Grande Valley, Texas

Tom Vezo / Yellow Warbler (Setophaga petechia) male taking flight, Rio Grande Valley, Texas

Konrad Wothe / Snow Goose (Chen caerulescens) pair flying over wetland, Bosque del Apache National Wildlife Refuge, New Mexico

Konrad Wothe / Snow Goose (Chen caerulescens) flying over wetland, Bosque del Apache National Wildlife Refuge, New Mexico

Konrad Wothe / Snow Goose (Chen caerulescens) flock flying over wetland, Bosque del Apache National Wildlife Refuge, New Mexico

Konrad Wothe / Snow Goose (Chen caerulescens) pair flying over wetland, Bosque del Apache National Wildlife Refuge, New Mexico

Konrad Wothe / Cowboy riding Domestic Horse (Equus caballus) is followed by two Dogs (Canis familiaris), Oregon

Konrad Wothe / Domestic Horse (Equus caballus) herd of five galloping across field, Oregon

Konrad Wothe / Cowboy riding a Domestic Horse (Equus caballus) beside pond with two dogs, Oregon

Konrad Wothe / Domestic Horse (Equus caballus) pair galloping, Oregon

Konrad Wothe / Cowgirl on Domestic Horse (Equus caballus) running through field, Oregon

Tim Fitzharris / Hot Creek at sunset, natural hot spring in Mammoth Lakes region, eastern Sierra Nevada, California

Tim Fitzharris / Hot Creek at sunset, natural hot spring in Mammoth Lakes region, eastern Sierra Nevada, California

Tim Fitzharris / La Plata River, La Plata Canyon, San Juan National Forest, Colorado

Tim Fitzharris / Ocean and lava rocks at sunset, Pu'uhonua, Hawaii

Tim Fitzharris / Ocean and lava rocks at sunset, Pu'uhonua, Hawaii

Tim Fitzharris / Ocean surf crashing on lava rocks at Molokini Crater, Maui, Hawaii

Tim Fitzharris / Court of the Patriarchs rising above river, Zion National Park, Utah

Tim Fitzharris / Firehole river, Yellowstone National Park, Wyoming

Yva Momatiuk & John Eastcott / Snow Goose (Chen caerulescens) flock flying in formation over wintering grounds, winter, Mattamuskeet National Wildlife Refuge, North Carolina

Tim Fitzharris / Gibbon River rapids popular river for trout fishing, Yellowstone National Park, Wyoming

Tim Fitzharris / Cascades tumbling 110 feet at Emerald Pools, note the black streaks called desert varnish, Zion National Park, Utah

Tim Fitzharris / Cascades tumbling 110 feet at Emerald Pools, note the black streaks called desert varnish, Zion National Park, Utah

Tim Fitzharris / Cascades tumbling 110 feet at Emerald Pools, note the black streaks called desert varnish, Zion National Park, Utah

Tim Fitzharris / Mt Spry at 5,823 foot elevation with the Virgin River surrounded by Cottonwood trees, Zion National Park, Utah

Tim Fitzharris / Mt Spry at 5,823 foot elevation with the Virgin River surrounded by Cottonwood trees, Zion National Park, Utah

Yva Momatiuk & John Eastcott / Gibbon River rapids, Yellowstone National Park, Wyoming

Yva Momatiuk & John Eastcott / Sand Bluebonnet (Lupinus subcarnosus) and Paintbrush (Castilleja sp) flowers in spring meadow, Hill Country, Texas

Yva Momatiuk & John Eastcott / Tundra Swan (Cygnus columbianus) large flock flying over Mattamuskeet National Wildlife Refuge, winter, North Carolina

Tim Fitzharris / Cascade and wildflowers at Yankee Boy Basin, Colorado

Tim Fitzharris / North Fork of the Virgin River flanked by Cottonwood (Populus sp) trees, Zion National Park, Utah

Tim Fitzharris / Lunch Creek Cascades, Glacier National Park, Montana

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) horses running, Red Desert, Wyoming

Yva Momatiuk & John Eastcott / Waterfall near Mammoth Hot Springs, Yellowstone National Park, Wyoming

Yva Momatiuk & John Eastcott / Waterfall near Mammoth Hot Springs, Yellowstone National Park, Wyoming

Gerry Ellis / Spring vine Maple leaves over Still Creek, temperate rainforest, Mt Hood National Forest, Oregon

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) herd running in dry, Dusty Desert, Wyoming

Bob Barbour / Terry Simms, central coast, California

Bob Barbour / Kevin Miske, central coast, California

Yva Momatiuk & John Eastcott / Snow Goose (Chen caerulescens) huge flocks flying at wintering grounds, spring, Bosque del Apache National Wildlife Refuge, New Mexico

Yva Momatiuk & John Eastcott / Snow Goose (Chen caerulescens) huge flocks flying at wintering grounds, early spring, Bosque del Apache National Wildlife Refuge, New Mexico

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) young stud colts, members of bachelor band, graze, play and fight together near Oshoto, northern Wyoming

Yva Momatiuk & John Eastcott / Mustang (Equus caballus) stallion charging to chase away intruder in summer, Montana

Gerry Ellis / Tanner Creek flowing through temperate rainforest, Columbia Gorge National Scenic Area, Oregon

Gerry Ellis / Downed logs in Sorensen Creek, temperate rainforest, Columbia Gorge National Scenic Area, Oregon

Tim Fitzharris / Merced River flowing through the valley floor, Yosemite National Park, California

Tim Fitzharris / Grotto Falls with the roaring Fork Motor Nature Trail passing beneath, Great Smoky Mountains National Park, Tennessee

Tim Fitzharris / Cascade near Grotto Falls, Great Smoky Mountains National Park, Tennessee

Tim Fitzharris / Grotto Falls, Great Smoky Mountains National Park, Tennessee

Tim Fitzharris / Punchbowl Falls at Eagle Creek, Columbia River Gorge, Oregon

Tim Fitzharris / Cascade along Eagle Creek flowing through temperate old growth rainforest, Columbia River Gorge, Oregon

Tim Fitzharris / Forest along Eagle Creek, springtime, Columbia River Gorge, Oregon

Tim Fitzharris / Latourell Falls, Columbia River Gorge near Portland, Oregon

Jim Brandenburg / Cascading stream, Great Smoky Mountains National Park, North Carolina

Flip Nicklin / White Tern (Gygis alba) landing with fish to feed to its chick, Hawaiian Leeward Islands, Hawaii

Jim Brandenburg / Timber Wolf (Canis lupus) running, Minnesota

Jim Brandenburg / Snow Goose (Chen caerulescens) flock flying at sunset, Mattamuskeet National Wildlife Refuge, North Carolina

Jim Brandenburg / Snow Goose (Chen caerulescens) flock flying, Mattamuskeet National Wildlife Reserve, North Carolina

Jim Brandenburg / Cascading stream flowing through Gifford Woods State Park in the autumn, Vermont

Jim Brandenburg / The New River cascading over Sandstone Falls, West Virginia

Jim Brandenburg / Cascading stream, Great Smoky Mountains National Park, North Carolina

Michael Quinton / Bobcat (Lynx rufus) running with captured Red Squirrel (Tamiasciurus hudsonicus) summer, Idaho

Norbert Wu / Golden Retriever (Canis familiaris) mix, shaking water from fur, California

Tim Fitzharris / Broad-tailed Hummingbird (Selasphorus platycercus) feeding on flowers, New Mexico

Tim Fitzharris / Snow Goose (Chen caerulescens) flock flying, Bosque del Apache National Wildlife Refuge, New Mexico

Michael Durham / Weed control signage along Highway 82, Wallowa County, listing introduced plants that have become invasive weeds, Oregon

Konrad Wothe / Dog (Canis familiaris) pair running with horses, Oregon