Luke and Sirius, two Spanish greyhounds, or galgos, are frolicking in their Alexandria, Virginia, backyard on a foggy October morning. Getting the playful dogs to stay still for a National Geographic photographer is hard enough, but when a squirrel scampers up a tree—impossible. Luke’s ears perk up, and he’s off.

The dogs have come a long way from Murcia, Spain, where they’d been abandoned. Good Samaritans found Luke and 10 other newborn puppies on the street with their mother in July 2013. Two months later Sirius was found on a road outside Murcia lying beside the corpse of another galgo, who had been shot. Sirius, perhaps a year and a half old, had stayed faithfully with his dead companion.

Galgos are an ancient breed of hunting dog once raised exclusively by Spanish nobles. Today they must be one of the most abused dog breeds on the planet. Tens of thousands are killed in Spain every year, often in gruesome ways. Countless more are abandoned.

Spanish Galgos: Finding Loving Homes for a Mistreated Breed WATCH: Paloma, a galgo, was rescued from the streets and now lives with her adoptive family in northeastern Italy. Thanks to the hard work of organizations like Fundación Benjamin Menhert, many galgos are getting a second chance. Warning: Graphic content.

They’re similar in appearance to greyhounds, with a smaller, lighter build, and have either smooth or shaggy coats. People who work with galgos say they tend to be loyal, kind, and affectionate.

“They're great dogs,” says Abigail Christman, founder of the Galgo Rescue International Network (GRIN), based in Colorado. “They're a greyhound with a sense of humor. They're a little more fiery, a little more sassy.”

Galgueros, the people who own and breed the dogs, use them for hare and lure coursing. In hare coursing—a controversial sport—the dogs race over the countryside or an enclosed track to catch the fleeing hare. Lure coursing replaces the hare with a mechanical lure. Galgueros hold coursing competitions every year between September and February. In the most prestigious of these, held in a different host city in Spain every January, the winning galgo takes home the Copa de Su Majestad el Rey, or King’s Cup, tacitly sponsored by the king of Spain himself, Felipe VI.

Galgos are mass-bred in hopes of finding that special courser. According to Tina Solera, founder of Murcia-based Galgos del Sol, the organization that rescued Luke and Sirius, dogs in many parts of the country are often kept in terrible conditions, chained outdoors in small concrete bunkers and fed just enough to keep them alive—and ravenous enough to give them an edge in competitions. “We've had galgueros that have had 70, 120 galgos, living on crisps and bread and eating each other when they die,” she says.

To train galgos for maximum speed, “a lot of times they'll take 12, 15 dogs out, tie them to the back of a motorbike or a car and run [them],” says Christman. “If one of them falls down or gets injured, too bad.”

Solera had never heard of galgos before she moved to Murcia from the U.K. in 2007 with her young family. Upon arrival, she was shocked by the sheer number of abandoned dogs on the streets and felt compelled to act. Galgos del Sol has rescued more than a thousand of the dogs since 2011.

Death by Horrific Means

After one or two hunting seasons, galgos who don’t measure up are killed—as many as 100,000 every year, according to Christman.

“It’s very hard to know how many are being killed because we don't know how many are being born,” Solera says. It’s the rampant, unchecked breeding—the dogs are rarely spayed or neutered—that leads to the high numbers of discarded galgos, as well as the fact that the dogs are only useful for such a short time. Because there’s a seven-month lull between hunting seasons, owners “don’t want to be bothering with them too much,” Solera explains.

Galgos have been thrown down wells, cast into rivers to drown, burned to death, and doused with acid. Some are left in forests, their legs intentionally broken so they can’t find their way home. “Last year we found one, and someone had gone at it with a pin hammer on the back of the skull,” recalls Marylou Hecht, director of both the U.S. branch of Galgos del Sol and of Galgo Podenco Support, a U.S.-based organization focused on facilitating American adoptions of galgos and podencos. (Podencos are a breed of hunting dog facing similar mass abandonment in Spain.)

And then there are the hangings. Dogs who have performed well in competition but are no longer in top form may be hanged high from a tree—a relatively quick death. Those who have embarrassed their galgueros by racing poorly may also be hanged, but low to the ground so their paws barely touch. Their desperate scrabbling for footing as they slowly choke to death is called “piano playing,” Christman explains.

Alistair Findlay of World Animal Protection, a U.K.-based animal welfare nonprofit, conducted a months-long undercover investigation on galgo hangings in the central province of Castile and León in 2003. “It was kind of like a family get-together,” Findlay says of the hanging sites. “The galgo owners would take food and drink with them, and you'd find the empty food cartons and bottles of wine nearby [the corpses].”

The Federación Española de Galgos, the leading national federation of galgueros, did not respond to multiple requests for comment.

Pilar Perez Martinez is a veterinarian in Murcia who regularly works with the rescued dogs at Galgos del Sol. She’s also a galguera. She says many galgueros love their dogs and would never harm them. She expresses frustration at the stigma galgueros face: “I feel attacked in many situations—for example, when I walk my galgos, and someone comes along to criticize me without knowing me or my animals. I think that hunters should be viewed separately from abusers,” she says.

‘The Key Is the Next Generation’

Conditions for galgos have improved somewhat in recent years. For one thing, Findlay says there are fewer hangings than there were when he conducted his investigation in 2003. New national laws against animal cruelty came into effect in 2004, 2007, and 2010, and a number of provinces and localities have passed similar legislation in recent years.

Yet despite high-profile prosecutions of a handful of galgueros who threw their dogs down wells, the perpetrators of the vast majority of galgo killings or abandonings never get punished because they’re hard to catch red-handed. “There’s nothing really on paper that’s concrete about what’s going on,” Solera says. Many dogs aren’t microchipped, and if they are, galgueros will often cut the chips out before they dispose of their dogs. And rescuers may not report crimes against galgos to the police for fear of retaliation. “It’s a really difficult balance,” Solera says. “It’s an ugly industry.”

Grassroots efforts are helping. Fermín Pérez, a science teacher who runs Scooby Medina, the largest animal shelter in Spain, has drawn international attention to the dogs’ plight. And Galgos del Sol is just one of many welfare groups to spring up in recent years that focus specifically on rescuing galgos. Others include Fundación Benjamin Menhert, based in Seville, and 112 Carlota Galgos, in Málaga.

View Images To travel to the U.S., Luke and Sirius got their own passports, identifying them by their original names, Bobby and Rubens. Some 150 galgos a year are adopted by Americans, and many more go to EU countries. Photograph by Rebecca Hale, National Geographic

Rescuing galgos alone isn’t an effective long-term solution, Solera says. The best hope in her view lies in public education. It’s a challenge, according to Hecht, who explains that the dogs don’t elicit much love in Spain. She recalls walking through an airport one day with some galgos she was bringing back to the U.S. for adoption. “People were throwing themselves against the walls, pointing and exclaiming, ‘Galgos, galgos!’ like they were hyenas. These are not dogs that are walked on leads.”

Galgos del Sol uses social media and billboards to promote galgo welfare, but they also take their message straight to the galgueros. “How could we ever possibly get on top of this if we don’t know what they're thinking?” Solera says. She attends galguero events to give speeches urging humane treatment and to hand out pamphlets. She talks with galgueros, encouraging them to rein in the rampant breeding.

For “generation after generation of Spanish people,” says Christman, of GRIN, “this is what their dad did, this is what their dad's dad did.” “The key is the next generation,” Solera says.

Galgos del Sol does a lot of work with kids in Murcia, including sponsoring a local bike racing team, the Galgo Warriors, outfitting them with uniforms and bringing galgos to watch their meets. The organization and other groups are introducing galgos to classrooms and teaching kids how to care for the dogs. According to Solera, for schoolchildren to be the most effective agents of change, animal welfare must be part of the national curriculum. That’s a challenge in a country emerging slowly from a crippling economic recession. “People haven’t got jobs, people are struggling, so it’s just no priority at all. But it doesn’t mean we can't try.”

Attitudes toward galgos are already changing in Barcelona and Madrid, where the dogs are becoming popular pets for young people. But, Solera says, it’s in largely rural regions like Murcia, where attitudes are deeply entrenched, that shifts are most meaningful.

“There used to be a time I couldn’t even leave the house without galgos being in the streets—that doesn’t really happen now,” she says, adding that although progress is slow, it is progress. “Our goal is to put ourselves out of business.”