A rescue team pulled a rare half-ton whale fossil from a Southern California backyard on Aug. 1, a feat that the team agreed to take on as a makeshift training mission.

The 16- to 17-million-year-old fossil from a baleen whale is one of around 20 baleen fossils known to exist, Natural History Museum of Los Angeles County paleontologist Howell Thomas said, according to the Associated Press.

The fossil, stuck in a 1,000-pound boulder, was lifted from a ravine by Los Angeles County Sheriff's Department search-and-rescue volunteers.

Crews pulled the fossil up a steep backyard slope and into a truck headed for the museum thanks to pulleys and a steel trolley.

The fossil was first discovered by Gary Johnson, 53, when he was a teen exploring the creek behind his family's home.

At the time, he called another nearby museum to come inspect the fossil, but officials passed on adding it to their collection.

Back in January, a 12-million-year-old sperm whale fossil was recovered at a local school, which got Johnson to the Natural History Museum.

"I thought, maybe my whale is somehow associated," said Johnson, who works as a cartoonist and art director, according to the Associated Press.

Thomas wanted to add the fossil to the county museum's collection of baleen whale fossils, but wasn't sure how to get the boulder from Rancho Palos Verdes, located on a peninsula about 25 miles southwest of downtown Los Angeles.

The search-and-rescue unit wouldn't send a helicopter, but offered to use the fossil recovery as a training mission.

Volunteer crews usually rescue stranded hikers and motorcycles who careen off the freeway into the steep and rough terrain, according to search-and-rescue reserve Chief Mike Leum said, according to the Associated Press.

"We'll always be able to say, 'it's not heavier than a fossil,'" Leum said.

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