IRVINE, Calif. (AP) _ A man who has contributed more than $500,000 for research into bighorn sheep bid $70,000 at an auction, winning the right to shoot one for the first time in California since 1873.

After the bang of the auctioneer's gavel awarded him a hunter's permit to take a single ram, Bob Howard, 46, of Palm Springs, said, ''I was just trying to build the bidding up and I got stuck.''

When pressed as to whether he would actually hunt a bighorn, Howard replied, ''I bought a tag, didn't I?''

Howard, a member of the institute's board, has contributed more than half a million dollars to his group to help preserve the bighorn, said Jim DeForge of the Bighorn Research Institute of Palm Desert.

The auction, sponsored by hunting and conservation organizations, drew about 300 people from throughout the United States to the world headquarters of the Fluor Corp., a multinational construction company.

A small group of protesters demonstrated outside, carrying placards that denounced hunting.

''They are just raising money to increase the number of animals so they can have more animals to kill,'' said Steven Zack, a spokesman for the Coalition of Animal Rights.

Bidders included affluent sportsmen aiming for a piece of the cherished ''grand slam.'' This is a hunter's prized collection of all four varieties of highly protected North American bighorn - desert, Rocky Mountain, Dall and Stone.

The auction, which has raffled off different hunts as well as fur coats, was expected to raise more than $250,000, said Ben Robson of the Society for the Preservation of Bighorn Sheep.

Howard's bid will go to the Department of Fish and Game for bighorn sheep research and management.

Shooting bighorns, along with antelope, elk and female deer, was banned in 1873 by the California Legislature when herds were depleted by market demand for meat, said Dick Weaver, a state bighorn sheep specialist. It was feared the animals faced extinction.

Today, California's bighorn herd numbers more than 4,700, a number deemed sufficient for a limited hunt by the state Fish and Game Commission, Weaver said.

Gov. George Deukmejian opened the way for the hunt last August when he took control of the bighorn herd away from a more protective Legislature and turned it over to the commission.

The commission, in turn, authorized a coalition of groups assembled by the Society for Conservation of Bighorn Sheep to hold an auction for a hunting tag allowing a single kill during a set 30-day period. All proceeds will go into the state's bighorn sheep conservation program.

Eight other single-kill permits, good for two weeks, will be issued to California residents through computerized random selection this fall. The deadline for application for the permits is Aug. 14; each permit recipient will pay a $200 fee.

Shooting a bighorn without a permit is punishable by a $10,000 fine and up to 10 years in prison, Weaver said.

In Montana, a bighorn hunting permit brought $109,000 to state coffers at an auction last January.

To get to the bighorns, a hunter typically will have to climb 1,000 feet up a steep and craggy incline in mountains that peak around 4,000 feet above sea level.

Once in position, the hunter could find the bighorn a relatively stable target, Weaver said.

''Bighorns typically like to take a look at what might be trouble for them, a bulldozer, whatever,'' Weaver said. ''It might be curiosity, it might be apprehension, they just don't immediately flee.''