PIERRE - A month after a state plane crashed and injured two people, conservation groups have asked South Dakota wildlife officials to scrap an aerial gunning program that kills coyotes that prey on cattle and sheep.

The program is dangerous for pilots and gunners, wastes taxpayer money and fails to control the coyote population, according to the petition delivered this week to South Dakota Game, Fish and Parks Department officials.

"It doesn't work," said Wendy Keefover-Ring of Sinapu, a Colorado-based group that organized the petition effort.

State officials are taking a comprehensive look at the aerial gunning program, but killing coyotes from airplanes is effective in removing those that are known to be causing problems for ranchers, said Emmett Keyser, assistant director of the Wildlife Division.

"There are problem coyotes. Where they are causing damage, that is where we try to focus our efforts for the most part," Keyser said. "Just killing coyotes doesn't help solve livestock damage problems. You've got to kill the right coyotes."

The Game, Fish and Parks Department will respond to the conservation groups' petition soon, Keyser said.

Many of the same conservation groups sent a similar petition asking the federal government to stop its aerial gunning program after a June 1 crash that killed two federal Wildlife Service employees who were hunting coyotes in Utah. The Wildlife Service has resumed the flights, but is taking steps to improve safety in the program, officials said.

In South Dakota, the pilot walked away with minor injuries and the gunner had a gash in his head after a crash landing while shooting coyotes.

Wildlife officials, pilots and other experts will conduct a thorough review of the accident and study whether changes are needed to make the aerial gunning program safer, Keyser said. If the program continues, officials will seek to make it as safe as possible, he said.

Keefover-Ring said the U.S. Agriculture Department's own research shows that when coyotes are killed, the animals adjust breeding practices to increase the population. Litters get larger, and more females have young, she said.

"We've been killing coyotes since the 1850s, and what we've done is expanded their range threefold," Keefover-Ring said.

"Lethal predator controls don't work. What we need the federal government and state agencies and others who fund predator control to do is invest in non-lethal, long-term solutions, commonsense things," Keefover-Ring said.

Ranchers could protect livestock by using protective structures to protect calves and lambs, using different fences, and placing guard animals such as dogs with the livestock, she said.

"It just makes more sense from a biological standpoint, from a fiscal standpoint and from a human safety standpoint to use non-lethal control," she said.

Of the 104 million cattle produced in the nation in 2005, only 0.18 percent were killed by predators, and only 3 percent of the 7.7 million sheep were killed by predators, Keefover-Ring said.

But Mike Held, executive director of the South Dakota Farm Bureau, said farmers and ranchers support the aerial gunning program because it helps when coyotes are killing calves or lambs in a particular area.

Keyser said the GF&P kills coyotes only when farmers and ranchers file complaints. Trapping and ground hunting are used in some cases, but aerial hunting is the fastest way to remove coyotes that are causing problems.

Removal of problem coyotes helps farmers and ranchers get through the calving or lambing season with fewer losses, Keyser said.

"It's an effective tool. There's no question about it," Keyser said. "We don't go out there with the idea of killing thousands of coyotes with the aim of annihilating the population. It's really more of a local control situation and trying to maintain a balance."

The groups seeking the ban on aerial gunning argue that the practice is inherently dangerous because it involves flying at low altitudes in situations where the pilots are distracted.

"Chasing animals from low-flying craft is so inherently dangerous that it should be stopped before any more public servants die," said Jeff Ruch, executive director of Public Employees for Environmental Responsibility, one of the groups seeking an end to aerial gunning.

Carol Bannerman, a spokeswoman for the federal Wildlife Services, said the agency killed about 75,000 coyotes in the 2004 federal fiscal year for a variety of reasons, such as protecting livestock, people and endangered species. In the same year, coyotes killed 134,500 sheep and lambs and 97,000 cattle and calves, she said.

Research suggests livestock losses would be much higher if predators were not controlled, Bannerman said.

"It's not our goal to eradicate coyotes. It is our goal to deal with particular damage problems," Bannerman said.

Since the fatal Wildlife Services crash in June, the agency has required additional inspections for planes, allowed pilots to identify risky areas where no flying will be conducted at certain times of the year, and planned additional safety training for pilots in the next few months, Bannerman said.

Pilots need a lot of experience before being hired by Wildlife Services, get additional training for low-level flight, and also get training on handling stalls and other potential problems, she said.

Aerial gunning was not resumed after the fatal June crash in six states where the season was coming to a close, but it was resumed in some other western states, Bannerman said.

Law enforcement, crop spraying, predator control and some other government activities involve some risk to employees, so the key is to make those activities as safe as possible while providing services to the public, she said.

The conservation groups' petition said aerial gunning is not only dangerous and ineffective, but also inhumane. Some coyotes are wounded and have to be shot several times, and the practice kills some adults that leave orphaned young, the petition says.

"Finally, and most importantly, coyotes have the inherent right to exist. To assume that we humans have the right to exploit them in the manner that is commonly practiced is without merit, immoral, ethically void, and inhumane," the petition says.