The DFG said it also is awaiting results of extensive genetic and disease tests to be conducted on a yearling bighorn ram that biologists were forced to kill Monday as it grazed with domestic sheep along the Warner foothills north of Cedarville. The animal and blood samples were delivered to officials of the Idaho Department of Fish and Game's Wildlife Health Laboratory for analysis.

"It is very exciting to realize that bighorn sheep may be back in the Warner Mountains, but very sad that we had to euthanize a juvenile ram," said Rich Callas, wildlife biologist in Siskiyou County.

The DFG said the yearling ram was shot Monday to guard against the possibility that it would contract disease from the domestic sheep and carry it back to bighorn bands in neighboring Oregon or Nevada — or to the small number of sheep reportedly using the Warners.

Bob Schaefer, DFG unit wildlife biologist in Alturas, said Fish and Game will take advantage of the availability of a helicopter early next year to search for bighorn. He said the decision to look for animals is partly based on photos of mountain sheep taken by residents of Cedarville.

The DFG said the origin of the bighorn reported to be in the Warners is not known. The animals likely immigrated into California from herds to the east in Nevada or to the north in Oregon. Oregon, Nevada and Idaho all have thriving bighorn populations that are regularly hunted, Fish and Game said.

If the presence of bighorn in the Warners is confirmed, Schaefer said, it would mark the first appearance of the species since a rapidly moving disease in 1988 wiped out a growing band of sheep the DFG had reestablished along the steep, scenic eastern slopes of the mountain range eight years earlier. The population had grown from 14 to more than 50 before bacterial pneumonia struck them down.

The 1980, Warner Mountains sheep introduction was composed of four bighorn sheep captured inside an 1,100-acre enclosure at Lava Beds National Monument near Tulelake and 10 other bighorn transplanted from the Sierra Nevada. Shortly after the relocation, all remaining 33 sheep inside the Lava Beds pen died, also from bacterial pneumonia.

In both the Lava Beds and Warner Mountains die-offs, the highly vulnerable wild sheep were killed by a form of pasteurella bacteria commonly in domestic sheep that are resistant to the disease. Also in both cases, domestic sheep were seen grazing in the vicinity of the wild bighorn before the disease outbreaks.

Before the Lava Beds and Warner sheep reintroductions, the northern end of California had gone without bighorn for more than 50 years. Domestic livestock grazing, water appropriations and market hunting dating back to the early 1800s were blamed for the disappearance of the centuries-old populations in the north state.

Presently, the state's bighorn populations include about 125 California sheep living in five small groups along the central Sierra Nevada —presently listed as endangered by both the state and federal governments — and two groups of desert, or Nelson, bighorn residing in California desert ranges.

The desert bighorn population comprises about 3,200 sheep of California's southeastern desert mountain ranges — where a limit of 10 hunting permits is issued annually — and another 400 "peninsular" bighorn to the south and west that are classified as threatened by the state and endangered by the federal system.

Members of mammal communities in the West dating back 150,000 years, bighorn sheep are believed to have reached North America via the Bering Strait. Outside of California, bighorn bands have been reestablished in Oregon, Washington, Idaho and Nevada using British Columbia stocks originally called California bighorn, but now more closely linked to Rocky Mountain bighorn.

The Lava Beds herd was created in 1971 with sheep from British Columbia.

Among the results DFG biologists hope to get from Idaho officials examining the Warner Mountains yearling ram is its genetic relationship with other sheep roaming the West. They also hope to learn if the yearling carried any genetic characteristics indicating it had resistance to some form, or forms, of the pasteurella bacteria.