Edwin Giesbers / RF- Konik Wild Horse (Equus ferus caballus) low angle close up of head. The Netherlands. July. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Grey Andalusian mare running in snow, Berthoud, Colorado, USA. January. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of grey Andalusian mare with long mane in snow, Berthoud, Colorado, USA. January. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild Mustang mare with sister and foal at Black Hills Wild Horse Sanctuary, South Dakota, USA. May. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild black Mustang filly leaping as pinto Mustang mother and friend follow, Black Hills Wild Horse Sanctuary, South Dakota, USA. June. (This image may be licensed either as rights managed or roy...

Carol Walker / RF - Head portrait of wild Mustang stallion tossing his mane while running, Black Hills Wild Horse Sanctuary, South Dakota, USA. February. (This image may be licensed either as rights managed or royal...

Carol Walker / RF - Wild buckskin Mustang stallion walking towards waterhole on dusty dry summer day, Sand Wash Basin, Colorado, USA. August. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild faded pinto Mustang stallion leaping through air in pursuit of another stallion, Sand Wash Basin, Colorado, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild Mustang stallion and family at waterhole in Sand Wash Basin, Colorado, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two wild Mustang horse families running to waterhole, Sand Wash Basin, Colorado, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of wild dunalino Mustang stallion with long mane, Sand Wash Basin Herd Management Area, Colorado, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two wild Mustang stallions, a sorrela and grey, fighting in Adobe Town, Wyoming, USA. June 2013. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild dun Mustang stallion running in Adobe Town, Wyoming, USA. October. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Old grey stallion standing alone in Adobe Town, Wyoming, USA. May. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of young wild grey Mustang stallion in Adobe Town, Wyoming, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Three wild Mustang bachelor stallions, head portrait of two pinto and one black meeting at waterhole, McCullough Peaks, Wyoming, USA. June. (This image may be licensed either as rights managed or...

Carol Walker / RF - Two wild Mustang stallions rearing in challenge, one pinto one grey in McCullough Peaks, Wyoming, USA. September. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two wild Mustang stallions face each other, one grey one sorral in McCullough Peaks Herd Area, Wyoming, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of wild Mustang stallion in profile, Pryor Mountains, Montana, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Three wild Mustang horses running in pasture, Pryor Mountains, Montana, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two white Camargue stallions rearing in play, Camargue, France, Europe. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Nine white Camargue horses running through water, Camargue, France, Europe. May. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - White Camargue stallion coming in from the sea, Camargue, France, Europe. May. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two Camargue horses coming in from the sea, Camargue, France, Europe. May. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Seven white Camargue horses running through water, Camargue, France, Europe. May 2014. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two wild Mustang stallions meeting in trees, Carrott Island, South Carolina, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild palomino Mustang stallion chasing bay bachelor away from his family, White Mountain, Wyoming, USA. August. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild Mustang palomino stallion rearing, White Mountain, Wyoming, USA. August. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild pinto Mustang stallion rearing, White Mountain, Wyoming, USA. August 2014. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Two Gypsy vanner geldings standing together looking away, Greyrock, Wyoming, USA. June. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Dapple grey Arabian stallion running in desert dunes near Dubai, United Arab Emirates. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of grey Arabian stallion in desert dunes near Dubai, United Arab Emirates. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Grey Arabain stallion trotting in desert dunes near Dubai, United Arab Emirates. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of black Merens stallion running in pasture, Northern France, Europe. February. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of grey Andalusian stallion standing quietly in arena, Northern France, Europe. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Dapple grey Andalusian stallion running in arena, Northern France, Europe. March. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Dapple grey Andalusian stallion running in arena, Northern France, Europe. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of black Andalusian mare and stallion meeting for the first time in Spain, Europe. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head portrait of grey Andalusian stallion running in pasture with windswept mane, Southern Spain. April. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Head and mane of grey Andalusian stallion running in bullfighting arena, Southern Spain, Europe. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF - Wild pinto Mustang stallion running in snow, Black Hills Wild Horse Sanctuary, South Dakota, USA. January. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Quarter horses running in snow at ranch, Shell, Wyoming, USA, February. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Pinto Quarter horse in snow at ranch, Shell, Wyoming, USA, February. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Two Wild mustang foals, sniffing noses. Pryor Mountains, Montana, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Herd of horses on ranch with mountains. Jackson Hole, Wyoming, USA. July 2011. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- White horse of the Camargue, running from sea. Camargue, Southern France (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Wild Mustang foal standing in wildflowers stretching. Pryor mountains, Montana, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Wild Mustang foal getting up from resting in wildflowers. Pryor mountains, Montana, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Wild Mustang bay running. Great Divide Basin, Wyoming, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Black Friesian stallion trotting. Ojai, California, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Bay Andalusian stallion running. Ojai, California, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Buckskin Andalusian stallion running. Ojai, California, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Herd of horses on ranch with distant mountains. Jackson Hole, Wyoming, USA. July 2011. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Wild Mustang horses, mare, juvenile and foal. Great Divide Basin, Wyoming, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Wild Mustang horses. McCullough Peaks Herd Area, Northern Wyoming, USA. June (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Andalusian stallion running, Longmont, Colorado, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Quarter horse, sorrel mare and foals. Double Diamond ranch, Nebraska, USA. July. (This image may be licensed either as rights managed or royalty free.)

Edwin Giesbers / RF- Silhouettes of two Konik wild horses (Equus ferus caballus). The Netherlands. July. (This image may be licensed either as rights managed or royalty free.)

Ross Hoddinott / RF- New Forest pony near Bratley View, New Forest, Hampshire, UK. November. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Mustang wild horse, bay foal running, Pryor Mountains, Montana, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Horses running in snow, Flitner Ranch, Shell, Wyoming, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Purebred Grey Andalusian mare looking out over snow, Longmont, Colorado, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Mustangs run at Return to Freedom Sanctuary, Lompoc, California, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Bay Andalusian stallion running in the snow. Berthoud, Colorado, USA. (This image may be licensed either as rights managed or royalty free.)

Carol Walker / RF- Palomino Quarter Horse Stallion (Equus caballus) head profile. Longmont, Colorado, USA. (This image may be licensed either as rights managed or royalty free.)

Ross Hoddinott / RF- Exmoor pony on Exmoor, Somerset, UK.

Carol Walker / RF- Grey Andalusian stallion head portrait. Colorado, USA. (This image may be licensed either as rights managed or royalty free.)