For the first time in two millennia, wild horses are once again galloping free in western Spain, countering what happened when the Romans moved there and domesticated the animals.
Four-dozen Retuerta horses have been released into the wild in western Spain over the past two years as part of a project by Rewilding Europe, a nonprofit group that seeks to turn the loss of rural farming life into an opportunity to boost biodiversity.
The endangered Retuerta is one of the oldest horse breeds in Europe and most closely resembles the race of ancient Iberian horses that populated this region before being domesticated.
Retuertas are nearly extinct, with only about 150 remaining in Doana National Park in southern Spain. Living in a single cluster there, the entire species could be wiped out by any potential disease or calamity.
So wildlife experts arranged to have two batches of two-dozen Retuertas each brought to the Campanarios de Azaba Biological Reserve, an unfenced area of western Spain that's believed to have once been native territory for the horses.
"Our idea is to just let them manage the ecosystem themselves. It's a wild horse. So it's in its DNA to roam free in the wild," said Diego Benito, a forestry engineer who lives and works at the reserve.
"Of course it is endangered close to extinction and we're conservationists," he added. "So if one of them gets ill, we could call the veterinarian. That's not the idea in the future we'll treat them like wild horses. But for now they could use a little care."
A Broader Effort To 'Rewild' Europe
The horse project at Campanarios is one of a half-dozen efforts sponsored by Rewilding Europe across the continent. Others include the rewilding of European bison, red deer, beavers, brown bears and white-tailed eagles in Romania, Poland, Slovakia, Croatia and elsewhere.
"In Europe, we live in a shadow land in a dim and flattened relic of what there once was, and of what there could be again," said George Monbiot, an environmental columnist for The Guardian newspaper and author of the recent book, Feral: Searching for Enchantment on the Frontiers of Rewilding.
"We've lost most of the big predators in Europe," he added. "We've lost all the big herbivores huge, elephant-sized rhinos used to live in Eastern Europe. We've lost a lot of our middle-sized herbivores. But this can be changed, and I think there's a very exciting future for rewilding here."
Spain is particularly suited to rewilding. The last Ice Age drove many native European species southward, and Spain retains high biodiversity with low human population density.
The Industrial Revolution drew rural human populations to big cities in northern Europe 300 years ago, yet Spain remained a relatively poor, agrarian society until the second half of the 20th century. Since then, the country has seen a massive migration to cities, particularly after the Spanish Civil War in the late 1930s, and now again during Europe's debt crisis.
The Landscape Changes
As Spaniards abandon rural life for the city, the land they've left behind is rewilding returning to a landscape unseen for centuries.
The first thing to come back is the underbrush, which used to be grazed by livestock but now grows unchecked and fuels increasingly dangerous wildfires growing in number and acreage in recent years.
"In the last 40 years, the bush has increased by more than 4 million hectares. That's nearly 10 percent of the country converted to bushland, because we lost the human population they went to the city," said Benigno Varillas, president of a subsidiary group, Rewilding Spain. "To control the bush, you need big animals herbivores to trample and graze. People have taken their horses and cows away. So this reintroduction [of wild horses] is very important."
Varillas tilts his cowboy hat and looks out over empty, overgrown hills that his relatives once farmed. These cork oaks and brush are vulnerable to wildfires. So Varillas and his conservationist colleagues are fighting them but not with water. They are rewilding the land with its natural protectors animals.
"If the domesticated herbivores are not anymore, then we need to bring in those who were there before," said Staffan Widstrand, marketing director for Rewilding Europe. "We had domesticated horses here. Well, previously there were wild horses."
The Retuerta horses are one example of the type of rewilding that could take place amid an unprecedented global migration to cities. In 1900, 13 percent of humans lived in urban areas; the United Nations forecasts that number will hit 85 percent in the developed world by 2050. Conservationists are looking at what all of those people leave behind animals, agriculture and ways of life and how to preserve it.
Varillas and Widstrand recently helped guide a group of foreign wildlife experts around the Campanarios de Azaba Biological Reserve. Once the group reached the crest of a hill, a ranch hand unlatched a metal gate, and out ran two-dozen Retuerta horses, trampling scrubby oak brush as they galloped down the hill and out over the horizon.