The base has brought in a geneticist from Texas A&M University to study whether its herd is among the very few genetically pure groups in the nation.
Most bison in the United States have at some point been bred with cattle to make them more palatable for human consumption.
But the Pendleton bison originally came from Yellowstone National Park, where a group of genetically pure bison still roam.
The San Diego Zoo, lacking room for them, gave the base 14 bison in the mid-1970s. The herd has grown to about 150 in the grassy northeast corner of 125,000-acre base. It is free to graze and wander in Pendleton's wide-open spaces.
"That's the beauty in my mind of our bison," Eric Kershner, the base's leader of wildlife management told the San Diego Union-Tribune. "They just do what they want. They are wild."
Officials at Camp Pendleton want to see if the herd is special enough to draw the interest of conservationists at a large preserve near Malta, Mont.
Marine Corps officials insist they like having the bison, but have been interested in thinning the herd and wouldn't mind shipping a few off to Montana. The bison sometimes wander into target range, forcing Marines to hold their fire and use air horns to scare them away.
"If we tried to do something in a negative way to get rid of them, it would be a PR nightmare," Kershner said.