Rare bison at Camp Pendleton studied to determine herd’s purity

By Mike Lee, STAFF WRITER
September 7, 2008

An unusual donation from the San Diego Zoo to Camp Pendleton may turn out to be more precious than anybody realized at the time.

In the early to mid-1970s, zoo officials gave the base 14 bison because they didn’t have enough room to keep the animals. The Camp Pendleton herd grew, and today, up to 150 bison live on the 125,000-acre Marine Corps installation - though few people outside the base know about them.

Bison is the proper name for the animal that American settlers called buffalo. Although there were an estimated 40 million in North America in 1800, a century later their numbers had dropped to 600. Through conservation efforts, they have increased to about 500,000 today.

Thanks to Camp Pendleton’s size, its group is among the few free-roaming bison herds in the nation. And thanks to the base’s isolation, the herd also may be among the most genetically pure. Most bison alive today have genes from ancestors that were bred with cattle to make them better for human food production.

The few genetically pure bison herds in the United States include those in the Yellowstone and Wind Cave national parks. Camp Pendleton’s bison are originally from Yellowstone and presumed to be plains bison, not their northern cousins known as wood bison, said Eric Kershner, leader of wildlife management for the base.

Marine Corps officials have hired James Derr, one of the nation’s top geneticists, to determine if their herd is pristine enough to interest conservationists who run a large reserve near Malta, Mont. Those preservationists might take some Camp Pendleton bison as part of their project to safeguard the species’ genetic integrity.

Derr, a professor at Texas A&M University, started testing the Camp Pendleton herd in July and will return in November for more study.

“We want to do our part,” Kershner said. “If we have an animal that’s useful to another program, we would like to participate.

“At the same time, reducing the animals potentially reduces some of the conflicts” with military training.

Base officials said the bison basically are left alone. The only intervention occurs when the animals periodically wander into target areas, causing Marines to stifle their gunfire and use air horns to encourage them to move out of harm’s way.

“That’s the beauty in my mind of our bison: They just do what they want. They are wild,” Kershner said.

Camp Pendleton’s leaders have considered thinning the herd through hunting, but haven’t moved ahead with the idea.

“If we tried to do something in a negative way to get rid of them, it would be a PR nightmare,” Kershner said.

Generally, California is not considered part of the modern bison’s habitat range. But the San Diego Natural History Museum has records of 11 fossilized bison that lived here about 100,000 years ago, when the region was probably much wetter and had more grassland, said Kesler Randall, who manages fossil vertebrate collections for the institution.

“If you go back far enough, they are native,” Randall said.

Almost all the fossils were found in Oceanside - just a few miles from Camp Pendleton.

Interest in the base’s herd is far greater today than it was three decades ago.

“The mammal curator at the San Diego Zoo called and asked me if we could accommodate some bison. . . . They had more than they could handle and they had canvassed every zoo in the country and nobody wanted them,” said Bill Taylor, now 96, Camp Pendleton’s natural resources director at the time.

The commanding general of the base accepted the offer, and the zoo donated five male and nine female bison to the base between 1972 and 1976.

The creatures were released into the northeast corner of the base, where rolling hills with grasses, oats and oak trees proved to be a good home.

Camp Pendleton was a ranch until it became a Marine base.

The bison also have a ready source of water at two ponds in an area called Case Springs, and they have numerous escape routes from the wildfires that routinely break out on base.

So as far as anyone knows, thick chaparral and steep terrain have kept the herd from roaming onto the adjacent Cleveland National Forest, said Mary Thomas, a biologist for the U.S. Forest Service’s Trabuco Ranger District.

Thomas recalled encountering the Camp Pendleton bison a few years ago while on the base researching habitat for steelhead trout.

“All of a sudden, the vehicle stopped and the guy who was driving said, ‘Uh, oh. I don’t know how long we are going to be here, but we need to wait until they decide which direction they are going to go,’ ” Thomas said. “You don’t want them to suddenly turn around and notice you because they are notoriously unpredictable.”
It’s not always easy to find the herd. The bison can evade even trained biologists for weeks at a time. Kershner has thought about attaching radio tags to some of the animals, but he ultimately decided it was too expensive. Occasionally, he does an aerial survey.

Bison rancher Ken Childs said base officials hired him about 20 years ago to assess their herd, which he found was becoming inbred and suffering from severe parasitic infestations. He doesn’t know what happened to his recommendations.

“I think for the well-being of the animals . . . they need to get a management program in place,” said Childs, who lives in Ramona.

Kershner hopes the current genetic study and related research about the herd’s health will form the basis for a long-term oversight plan.

One recent morning, he and colleague Roland Sosa used a four-wheel drive vehicle to scale steep dirt roads on the farthest reaches of the base.

Signs of bison were everywhere: matted grasses where they had walked, thick patties of dung, a putrid carcass with bleached bones.

Around a bend, several hulking brown bodies of bison rose from the parched grass. The biologists counted nearly 20 of the creatures, who stirred lazily and walked away as the men trained their binoculars on them.

Somewhere below, Marines could be heard training on firing ranges. The base is home to upward of 35,000 service members and their families.

With their humped backs, horns and rugged appearance, bison are among the most recognizable animals in the West.

In 1800, about 40 million of them roamed the midsection of North America, mowing the prairie, fertilizing vast areas with their feces and becoming food for grizzly bears and American Indians.

Fewer than 600 bison were left on the continent a century later, according to the National Park Service. The reasons for their decline include hunting by settlers in addition to the Indians, along with U.S. government programs to control Indian tribes by practically wiping out their main source of food.

Thanks to conservation efforts, about 500,000 bison live today on private ranches and public lands such as wildlife refuges.

Thomas Roffe, a leading bison expert for the U.S. Fish and Wildlife Service in Montana, said he knows of only two herds in California that have more than 100 bison - the one at Camp Pendleton and another of similar size on Catalina Island.

About 500 bison live in San Diego County and Camp Pendleton’s herd is the largest, said Childs, the bison rancher in Ramona.

In 2005, the World Wildlife Fund and the American Prairie Foundation released genetically pure bison on what is now an 80,000-acre wildlife reserve in northern Montana. The groups want to restore a piece of the Great Plains ecosystem and gather information about how best to manage bison and their native landscape.

“Since we don’t know what the implications are (of cattle genes) and they may be potentially negative, . . . we are interested in the cleanest animals out there,” said Kyran Kunkel, a senior fellow at the World Wildlife Fund in Bozeman, Mont.

At Camp Pendleton, Kershner expects the genetic testing to be completed by January. He hopes to send some of the herd to Montana or other reserves.

“If they are pure, people are going to be wanting them,” Kershner said.

BASE SPECIES
Camp Pendleton is home to many animals besides bison. They include:

Arroyo toads
Badgers
California least terns
Coyotes
Deer
Mountain lions
Pacific pocket mice
Red-tailed hawks
Roadrunners
San Diego fairy shrimp
Tidewater gobies
Western snowy plovers

SOURCE: Camp Pendleton

BISON FACTS

Commonly called buffalo
Lives on about 4,000 ranches and on several wildlife refuges in the United States
Life span of 20 to 25 years
Hair can grow to 16 inches
Weighs 1,100 to 2,000 pounds
Runs as fast as 30 mph
Eats pasture grasses and prairie hay
Cow generally has one calf a year
Calves can walk or run hours after birth
Sales of bison meat totaled $286 million in 2007

SOURCES: National Bison Association; National Park Service
U-T Multimedia: For video of researchers tracking bison at Camp Pendleton, go to uniontrib.com/more/bison.

Mike Lee: (619) 542-4570; mike.lee@uniontrib.com
© Copyright 2008 Union-Tribune Publishing Co.

Posted on September 7th, 2008 by hunwut
Filed under: Environment