RENO, Nev. (AP) - Sheryl Crow has spoken out against the war in Iraq and in support of embryonic stem-cell research and efforts to combat global warming. Now, she's trying to ride to the rescue of thousands of wild horses that roam the West.

After campaigning for President Barack Obama in 2008, the Grammy-winning singer has become a leading critic of his administration's plans to remove as many as 25,000 mustangs from the range and ship them to pastures in the Midwest and East.

Since coming out in favor of a moratorium on government roundups of mustangs in November, Crow has lobbied Interior Secretary Ken Salazar, dropped off books and DVDs about wild horses for Obama at
the White House and appeared in a video produced by equine activists.

To no avail, she also called on the president to halt a roundup of about 2,500 mustangs in Nevada, which began late last month as part of the administration's strategy to remove thousands of mustangs from the range.

"My main concern is that horse numbers not be dwindled down to where they can become extinct," she said, fearing the roundups are
leaving mustang herds with too few breeding horses.

The government says the number of wild horses and burros on public lands in the West stands at nearly 37,000, about half of them in Nevada. It believes the number that can be supported on the range is about 26,600.

An additional 34,000 wild horses already live away from the range in federal-run corrals and pastures. Those are nearly full at a growing cost.

In an interview with The Associated Press, Crow said the romantic symbols of the American West are being sacrificed, in part, because of ranchers' drive for land. She disputed the government's position that booming mustang numbers are threatening the horses with starvation, and harming arid rangelands and native wildlife.

"I think there has to be a better way than taking them away from their native lands," she said by phone from New York. "I feel so passionate about the issue because wild horses are one of the last remaining ties to the land as it was and our history in America."

The 47-year-old rocker became acquainted with the issue when she rode an adopted wild horse named Smokey in Colorado's Sangre de Cristo Mountains in July 2006, several months after she and cycling champ Lance Armstrong broke off their engagement.

Crow was joined on rides there by friends, including Ginger Kathrens, executive director of the horse-advocacy group Cloud Foundation based in Colorado Springs, Colo. Kathrens is an Emmy-winning documentary filmmaker who has produced PBS programs on a wild stallion named Cloud.

"Sheryl fell in love with the mustangs," Kathrens recalled. "We sat and talked about how we were losing the mustangs (to government roundups). She asked, `What can I do to help?"

Kathrens credited Crow for "jump-starting" the movement for a roundup moratorium and bringing widespread media attention to the issue. Nearly 150 organizations have endorsed the request. "Sheryl is a big star and when she says this is something we should be doing the media perks up," Kathrens said.

Since the rides in the Sangre de Cristos, Crow has adopted a wild mustang named Colorado. She has 20 other horses on her ranch near Nashville, Tenn.

"I was the kid who asked for a horse every year, but we didn't have the backyard for one," the Kennett, Mo., native said. "Now, I ride every day I'm at the ranch. It's a very spiritual connection riding a horse."

Salazar said Crow's passion for horses came across in a phone conversation last month, which he initiated at the urging of his staff after she called for the moratorium. "I told her we didn't know we had the right solution here, but it was the solution we were offering and if there were other ideas we would be happy to entertain those ideas," he said.

Crow said she was pleased that Salazar pledged to open lines of communication with equine activists, but disappointed he ignored her plea to halt the roundups. While she will continue to press for the moratorium, she has no plans to talk to Obama. "He has enough on his plate," she said.

Meanwhile, there are other celebrities pushing the cause, including Willie Nelson, Lily Tomlin, Bill Maher and Ed Harris.

Ron Cerri of the Rebel Creek Ranch near Orovada, Nev., said Crow and the other celebrities are "outsiders" who are unfamiliar with problems caused by the mustangs. He supports the administration's plan, saying the horses are hurting the range, native wildlife and livestock because they can double in population every four years.

"It's not only about the health of the range and the resources, but the health of the horse herds," said Cerri, who is president of the Nevada Cattlemen's Association. "It disappoints me it's not a consideration to them. It's an emotional issue to them."