SIOUX CITY, Iowa (AP) _ Kathy Faber was nervous when she introduced llamas to her flock of sheep.

``I thought, boy, this is going to scare those sheep right through the fence,'' she recalled. ``But nothing happened. The sheep kind of sniffed them and said, `Eh, another sheep.'''

Which proved one thing right away.

Sheep ``really ARE stupid,'' Faber said. ``They couldn't survive on their own. When you read about them in the Bible, they always have shepherds. They can't do anything themselves.''

Two years later, the llamas have proved themselves as guards. Faber hasn't lost a single sheep to predators ever since llamas Norman and Spice were added to the flock.

Dogs are still the guards of choice among sheep ranchers, but more and more are using llamas.

``Dogs aren't as easy to manage. They tend to roam, and people tend to shoot them,'' said Dan Morrical, a sheep specialist for the Iowa State University Extension Service. ``On the other hand, llamas eat what sheep eat, they bond with sheep, and they'll run off canines.''

The extension service interviewed 145 llama-owning sheep ranchers across the country and found that 85 percent recommended the South American animals. Only 1 percent were unhappy with the llamas.

About 5 percent of Iowa's 6,000 sheep producers use llamas as guards.

Faber said her sheep, especially the lambs, were continually threatened before she got llamas to patrol her hilly and wooded 80-acre farm. The place is loaded with coyotes.

``You can hear the pack howling. Oooh, they give you the creeps,'' she said.

Faber watched one day as a stray dog entered one of her pastures.

``The llamas took after him. Let me tell you, that dog was running with its tail between its legs. I never saw it again. Usually, you see a dog once, you'll see it again,'' she said. ``Not this dog.''

Llamas are not predators themselves, but they present a problem for coyotes.

``A coyote weighs 25 pounds. You got that 300-pound llama,'' Morrical said. ``They'll hold their ground. They'll spit, they'll paw. The coyote looks at that llama and says, `Maybe not.'''

Not all llamas are suited for the job. The survey found cases in which the animals tried to mount the ewes. A few became over-protective, keeping the rancher along with the coyotes at bay.

But Faber said her llamas have been nothing but helpful in managing her 34 sheep.

``That first year was a blast,'' she said. ``These guys would lie down on the ground and let the baby lambs crawl all over them and lay in a pile on them, like they were playing king on the mountain. These guys, they work so well together.''