Jack Dykinga / Bald eagle (Haliaeetus leucocephalus) perched, Bosque del Apache National Wildlife Refuge, New Mexico, USA.

Claudio Contreras / California condor (Gymnogyps californianus), portrait. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico.

Claudio Contreras / California condor (Gymnogyps californianus), two perched in tree, adult and juvenile. California condor recovery program, Sierra de San Pedro Martir National Park, Baja California Peninsula, Mexico.

Jack Dykinga / Sandhill cranes (Antigone canadensis) taking off in dawn light. Bosque del Apache National Wildlife Refuge, New Mexico, USA, January

Jack Dykinga / Bald eagle (Haliaeetus leucocephalus) perched as Snow geese (Chen caerulescens) fly by, Bosque del Apache National Wildlife Refuge, New Mexico, USA, January.

Jack Dykinga / Snow goose (Chen caerulescens) landing into a tight packed flock on lake, Bosque del Apache National Wildlife Refuge, New Mexico, USA. January.

Jack Dykinga / Sandhill cranes (Antigone canadensis) feeding in pond, Bosque del Apache National Wildlife Refuge, New Mexico, USA. January.

Jack Dykinga / Snow goose (Chen caerulescens) landing into flock, Bosque del Apache National Wildlife Refuge, New Mexico, USA, January.

Jack Dykinga / Sandhill cranes (Antigone canadensis) taking off and flying past a full 'super-moon' en route to feeding in neighboring fields. Bosque del Apache National Wildlife Refuge, New Mexico, USA, Jan...

Jack Dykinga / Sandhill cranes (Antigone canadensis) and Snow geese (Chen caerulescens) at sunrise, Bosque del Apache National Wildlife Refuge, New Mexico, USA, November.

Jack Dykinga / Sandhill cranes (Antigone canadensis) in flight in late evening light, Bosque Del Apache, New Mexico, USA. December

Jack Dykinga / Flocks of Mallard ducks (Anas platyrhynchos) taking off in tree-lined wetlands. Bosque del Apache National Wildlife Refuge, New Mexico, USA.

John Shaw / Western screech owl (Megascops kennicottii) is camouflaged as it looks from a tree cavity. Bosque del Apache National Wildlife Refuge, New Mexico, USA, January.

Claudio Contreras / Central American spider monkey (Ateles geoffroyi) juveniles hanging by tails and playing, Calakmul Biosphere Reserve, Yucatan Peninsula, Mexico, August

Jeff Foott / Wild California condor (Gymnogyps californianus) near San Pedro Martir National Park, Northern Baja California, Mexico.

Jack Dykinga / Sandhill cranes (Grus canadensis) landing at sunset, blurred motion, Bosque del Apache National Wildlife Refuge, New Mexico, USA.

Jack Dykinga / Sandhill cranes (Grus canadensis) flying in to land at sunset in golden light, Bosque del Apache National Wildlife Refuge, New Mexico, USA, December.

Jack Dykinga / Snow geese (Chen caerulescens) large flock with some landing, Bosque del Apache, New Mexico, USA, December.

Jack Dykinga / Sandhill crane (Grus canadensis) running to take off into flight, Boque del Apache, New Mexico, USA, December.

Jack Dykinga / Sandhill cranes (Grus canadensis) mating dance at sunset, Bosque del Apache National Wildlife Refuge, New Mexico, USA, December.

Jack Dykinga / Snow geese (Chen caerulescens) in flight in front of super moon, Bosque del Apache National Wildlife Refuge, New Mexico, USA, December.

Jack Dykinga / Sandhill cranes (Grus canadensis) and Snow geese (Chen caerulescens) Bosque del Apache National Wildlife Refuge, New Mexico, USA, December.

Jack Dykinga / Yuccas (Yucca elata) silhouetted against the moon and morning light, White Sands National Park, New Mexico. January.

Jack Dykinga / Snow geese (Anser caerulescens) flying toward their gathering pond, with moon in the background, Boque del Apache National Wildlife Refuge, New Mexico. December.

Jouan Rius / Gypsum sand dune at sunset, White Sands National Park, Chihuahuan Desert, New Mexico, USA, December 2012.

Jack Dykinga / White Sands National Park with its white gypsum dunes dotted with Yuccas (Yucca elata) creating patterns amid the dunes, at sunset. White Sands, New Mexico. January 2013

Jack Dykinga / White Sands National Park with its white gypsum dunes dotted with Yuccas (Yucca elata) creating patterns amid the dunes. White Sands, New Mexico, USA. January 2013

Jack Dykinga / Sandhill crane (Grus canadensis) landing in icy pond filled with snow geese (Chen caerulescens) Bosque del Apache, New Mexico. January 2013

Floris van Breugel / Various fluorescent minerals : 1Willemite, New Jersey, 2: Willemite and Calcite, New Jersey, 3: Fluorite, Ohio, 4: Willemite and Calcite, New Jersey. 5: Fluorite, California. 6: Scheelite, California....

Daniel Heuclin / Round-tailed Horned Lizard (Phrynosoma modestum) on rocks, near Alamogordo, New Mexico, USA, April

Danny Green / Snow Goose (Chen caerulescens), coming in to land. Bosque del Apache, New Mexico, USA, November.

Danny Green / Snow Geese (Chen caerulescens) in flight, silhouetted against colourful dusk sky. Bosque del Apache, New Mexico, USA, November.

Carol Walker / Girl stroking donkey (Equus asinus) New Mexico, USA, September 2011, model released

Konrad Wothe / Mixed flock of Snow geese (Chen caerulescens atlanticus / Chen caerulescens) and Sandhill cranes (Grus canadensis) at wintering area at dawn, with full moon, Bosque del Apache, New Mexico, USA, Novemb...

Konrad Wothe / Flock of Snow Geese (Chen caerulescens atlanticus / Chen caerulescens) in flight to their winter roosting site, crossing a full moon, Bosque del Apache, New Mexico, USA, November

Konrad Wothe / Three Snow Geese (Chen caerulescens atlanticus / Chen caerulescens) in flight, Bosque del Apache, New Mexico, USA, November

Charlie Summers / Three Snow Geese banking and gliding in preparation for a landing (Chen caerulescens). Bosque del Apache, New Mexico, January.

Daniel Heuclin / Rio Grande Cottonwood tree (Populus fremonti wislizenii) on a sand "pedestal" White Sands National Park. New-Mexico, USA, August 2009

Floris van Breugel / View of snow-like dunes of the White Sands National Park. These sand grains consist of tiny crystals of gypsum. New Mexico, USA, April 2010

Jack Dykinga / Roots of Fig trees (Ficus sp) growing in the collapsed Cenote Oxpeejool (sink hole), near Tekax, Yucatan, Mexico. Afternoon light illuminates the elongated cavern on the right. October 2009

Patricio Robles Gil / Barrel cactus (Ferocactus pilosus) Chihuahuan desert, Mexico

David Tipling / Snow geese {Anser / Chen caerulescens} flock taking off, Bosque del Apache, New Mexico, USA, January

Andy Rouse / Aerial view of a large flock of Snow geese (Chen caerulescens) on lake, Bosque del Apache, New Mexico, USA

Andy Rouse / Snow geese (Chen caerulescens) landing, Bosque del Apache, New Mexico, USA

Andy Rouse / Flock of Snow geese (Chen caerulescens) taking off, Bosque del Apache, New Mexico, USA

Andy Rouse / Large flock of Snow geese (Chen caerulescens) taking off, Bosque del Apache National Wildlife Refuge, New Mexico, USA

Jack Dykinga / Tent rocks in the Peralta Canyon, New Mexico, USA. Rocks are conical formations of eroded volcanic tuff and pumice supporting 'cap rocks'.

Rob Tilley / White sand dunes against blue sky, White Sands National Park, New Mexico, USA, February 2009