Seven blind mustangs with bloodlines that stretch back to Spanish explorers will live out their days in Minnesota.

This Old Horse, a nonprofit horse sanctuary in Dakota County, agreed to care for the seven blind stallions, as well as two mares, which had been living at an overcrowded horse sanctuary in South Dakota.

A local horseman and his crew picked up the horses last week and brought them to the nonprofit's Wishbone Ranch just outside of Hastings. The ranch, already home to two blind horses, is equipped with special plastic pipe fencing that won't injure the animals if they bump into it, said Pete Swentik, program director for This Old Horse.

"The alternative was they would be euthanized," Swentik said.

The nonprofit is a partner with the University of Minnesota Extension Horse program. Swentik said he's hopeful the U will take an interest in Wishbone Ranch's newest residents, which have an undiagnosed eye problem.

"We don't know anything about their blindness until we have someone look at them," Swentik said. "We don't know if it's heredity or environmental."

The mustangs are descendants of Spanish horses brought to North America in the 1500s. Those horses became wild and have wandered the western United States for centuries.

In 1996, the U.S. Bureau of Land Management planned to remove dozens of wild horses near Gila Bend, Ariz. The International Society for the Protection of Mustangs and Burros, a private sanctuary in Lantry, S.D., took them in but now says it's unable to maintain enough habitat for more than 800 animals.

That's why This Old Horse agreed to care for some of the most vulnerable among them.

Founded by Nancy Turner in 2012, This Old Horse currently cares for about 40 retired, rescued and recovering horses.

"We are generally a retirement, surrender and rehab facility," Swentik said.

People who can no longer care for their horses can turn them over to the nonprofit. Performance horses with medical problems also reside there, including relatives of Triple Crown winners Secretariat and Seattle Slew.

There's a waiting list of people seeking to surrender horses. "This is a place where the horses could retire and be honored for the service they gave us," Swentik said.

The nonprofit relies on a core group of 100 volunteers who feed and care for the horses twice daily. They have fewer than 10 paid employees.

Visitors can tour Wishbone Ranch and see the new horses at a free open house from 10 a.m. to 4 p.m. on Sat., Nov. 12, and on Sat., Dec. 10. The ranch is at 19025 Coates Blvd., Hastings.

"They look distinctive," This Old Horse spokeswoman Monica Carlson said of the new mustangs. "They are smaller than Quarter horses and they have more of a Roman face. And they are little shaggier."