Eric Kershner, wildlife management leader for Marine Corps Base Camp Pendleton, said since the zoo gave the southern California site 14 bison in the 1970s, that herd's population has helped increase the nationwide population of the animals, the San Diego Union-Tribune reported Sunday.

While the number of Camp Pendleton bison has grown to nearly 150, similar preservation efforts nationwide have helped the U.S. bison population reach nearly 500,000 after teetering on the brink of extinction at the turn of the 20th century.

The U.S. bison population numbered an estimated 40 million in 1800 before being decimated by hunters.

The Pendleton herd should continue to grow as Kershner told the Union-Tribune the animals will remain safe from hunting due to public relations considerations.

"If we tried to do something in a negative way to get rid of them, it would be a PR nightmare," he told the newspaper.