More than 30 hawks and owls were trapped and killed at a private Lowcountry plantation to keep them from preying on quail that were released by the thousands for hunting, an egregious example of what one federal prosecutor called a widespread practice in the Southeast.

Three employees of MacKay Point Plantation in Jasper County pleaded guilty Friday to unlawfully trapping and killing red-tailed hawks, Cooper's hawks and great horned owls from 2012 to 2014. The pleas were taken in U.S. District Court, Charleston. As part of plea agreements, they paid fines and will perform community service, among other stipulations.

The plantation owners agreed to donate $250,000 to animal charities including the Center for Birds of Prey in Awendaw and the Harry Hampton Wildlife Fund.

Taking, killing or trading birds of prey violated the Migratory Bird Treaty Act. The charges were federal misdemeanors, but the maximum fines could have been six months in prison and $15,000 fines.

William Martin, 59, of Yemassee, the plantation manager, paid a $1,000 fine, and admitted to setting traps. Keith Gebhardt, 54, also of Yemassee, a plantation dog trainer, paid a $500 fine and admitted to setting traps. Mark Argetsinger, age 63, of Beaufort, a heavy equipment operator, admitted to rounding up and killing trapped birds.

Each of the men must perform 25 hours of community service.

Dozens of traps were set, prosecutors said.

"This is one of the most serious wildlife cases in state history, and we hope it will send a deterrent effect,"said Assistant U.S. Attorney Rhett Dehart. Prosecutions of other plantations are in the works, he said.

MacKay Point Plantation is an 8,000-acre "state-of-the-art hunting preserve," according to prosecutors, along the Tullifinny River. Deer, doves and ducks also are hunted. It is owned by Florida businessmen Bruce Anderson and Patrick Welsh and used by the owners and guests. Investigation found no evidence the owners were involved, DeHart said.

Among the plantation's guests have been then-Vice President Dick Cheney, who hunted quail in 2004.

Historically, hawks and other birds of prey were shot out of the air as varmints for generations by country landowners to keep them from their poultry. The problem has been exacerbated by modern approaches to bird hunting, in which pen-raised game birds are released en masse and are virtually helpless in the wild.

At the MacKay Plantation, about 6,000 quail were released per year for the winter hunting season, according to the statement of fact read by DeHart.

"If you asked me how to attract birds of prey, I'd say release thousands of (pen-raised) quail. Like other predators, birds of prey are opportunists. It's a cultural reality that the (management) approach taken way too often is to shoot every bird of prey on sight," said Jim Elliott, Center for Birds of Prey director. "It's not just the Southeast, it's wherever there are quail."

But the raptors take only a small percentage of quail, he said. A recent study surprisingly found the biggest predator of quail are armadillos that eat eggs out of the nests.

Nathan Dias, Cape Romain Bird Observatory director, said the approach also is self-defeating. Birds of prey feed on snakes, rodents and other animals that kill more quail than the birds.

Gebhardt, in his plea statement, said, "It was wrong to do. I knew I shouldn't have done it. But it did improve the quail hunting."

According to the statement of fact, S.C. Department of Natural Resources and U.S. Fish and Wildlife officers began investigating after receiving a confidential tip and finding a dead hawk near the plantation riverbank. Surreptitious surveillance cameras caught the men in the act.

The trapping "is more gruesome than shooting the hawks and owls because the birds were often trapped for several days before being killed," the statement read.

U.S. Magistrate Judge Bristow Marchant said given the time birds were left in the traps, the two years of violations and the number of raptors involved, he likely would have issued harsher sentences except for the plea agreement and the owners' donation.

"Every living creature feels pain and is capable of suffering," he said. "Trying to make sure employers have good hunting is no excuse" for the conduct.

Elliott, who was not at the hearing, said 12 percent to 15 percent of birds of prey admitted to the center show evidence of gunshots, some birds shot more than once.

"It's a challenge" to overcome that cultural predisposition, to get people to see the importance of the birds to the ecosystem, he said. Over the course of 23 years working in the field, he has seen a positive shift in attitude toward birds of prey. People who shoot them "are becoming the exception. But they're still out there."

Reach Bo Petersen at 937-5744, @bopete on twitter or Bo Petersen Reporting on Facebook.