Chadden Hunter / Dallol hot springs where water heated by magma laden with potassium, sulphur and iron spews up through salt pans staining the salt deposits with vivid colours, in the bottom of the Rift Valley, 120 me...

Tom Vezo / Red-tailed Hawk (Buteo jamaicensis) adult rufous morph flying, Sulphur Springs Valley, Arizona

Tom Vezo / Prairie Falcon (Falco mexicanus) at banding station, Sulphur Springs Valley, Arizona

Chadden Hunter / Dallol hot springs where water heated by magma laden with potassium, sulphur and iron spews up through salt pans staining the salt deposits with vivid colours, in the bottom of the Rift Valley, 120 me...

Chadden Hunter / Dallol hot springs where water heated by magma laden with potassium, sulphur and iron spews up through salt pans staining the salt deposits with vivid colours, in the bottom of the Rift Valley, 120 me...

Chadden Hunter / Cameraman, Martyn Colbeck, filming the Dallol hot springs where water heated by magma laden with potassium, sulphur and iron spews up through salt pans staining the salt deposits with vivid colours, i...

Jack Dykinga / Saltgrass (Distichlis spicata) with Lizard Tail (Anemopsis californica) in foreground, Warm Sulphur Springs, Death Valley National Park, California

Jack Dykinga / Spires of Chiricahua National Monument sprinkled with early snow, double summit of Dos Cabezas Mt and Sulphur Springs Valley in background, Arizona, USA

Philippe Clement / Calcite springs and the Yellowstone river, Yellowstone NP, Wyoming, USA

Philippe Clement / Calcite springs and the Yellowstone river, Yellowstone National Park, USA

Tom Vezo / Ferruginous Hawk (Buteo regalis) juvenile light morph flying, Sulphur Springs Valley, Arizona

Tom Vezo / Prairie Falcon (Falco mexicanus) close-up portrait at banding station, Sulphur Springs Valley, Arizona

Tom Vezo / Swainson's Hawk (Buteo swainsoni) perched on fencepost, Sulphur Springs Valley, Arizona

Tom Vezo / Red-tailed Hawk (Buteo jamaicensis) adult rufous morph flying, Sulphur Springs Valley, Arizona

Tom Vezo / Red-tailed Hawk (Buteo jamaicensis) on ground with wings spread open, front view, Sulphur Springs Valley, Arizona

Tom Vezo / Red-tailed Hawk (Buteo jamaicensis) adult rufous morph perching, Sulphur Springs Valley, Arizona

Tom Vezo / Ferruginous Hawk (Buteo regalis) on ground, Sulphur Springs Valley, Arizona

Tom Vezo / Prairie falcon {Falco mexicanus} C Arizona USA at banding station Sulphur springs

Tom Vezo / Ferruginous hawk flying {Buteo regalis} Arizona USA sulphur springs valley

Tom Vezo / Prairie falcon held at Banding station {Falco mexicanus} Arizona USA sulphur springs

Tom Vezo / Prairie falcon {Falco mexicanus} C Arizona USA at banding station Sulphur springs

Tom Vezo / Ferruginous hawk {Buteo regalis} Arizona USA sulphur springs valley