SAN FRANCISCO — He shot squirrels in the head so their bodies would be intact for meals.

He caught frogs, lizards and a 2-foot brown snake, killing them with a rock and toasting them thoroughly so he would not get salmonella.

Each night, before burying himself under rotting leaves, he carefully covered his fire with gravel to prevent it from spreading.

Gene Penaflor made it through 19 days lost in the wilds of Northern California’s Mendocino National Forest by going into “survival mode,” his son, Gale Penaflor, 37, said Monday.

The 72-year-old retiree was back home in San Francisco, 13 pounds lighter than when he disappeared and his voice raspy, but otherwise in excellent health, his family said. Penaflor got lost during a deer hunting trip in treacherous terrain marked by jagged cliffs and slippery shale and shrouded by thick fog. Other hunters discovered him on Saturday.

“Mentally, he was telling us, he was in survival mode,” Gale said. “He really wasn’t thinking about anything else. Trying to stay alive kept him busy, and that is what kept him going.”

Penaflor, a native of the Philippines, and a longtime friend were camped at 6,000-foot elevation when they separated to stalk deer. Penaflor’s companion reported him missing in an area known as Bloody Rock early on Sept. 24. Penaflor had fallen into a crevice, hit his head and lost consciousness. He awoke disoriented in the fog, the Mendocino sheriff’s office said.

“I thought my kneecap was broken,” Penaflor told reporters Sunday. “After that all went dead. I was passed out. I don’t know for how long.”

Authorities said Penaflor walked around for a while before realizing he was lost and made a camp under a tree near a stream. The son said his father had two garbage bags with him and wore them to keep himself dry. Temperatures dipped to 25 degrees. “He said his boots were really key,” Gale said. “They’re Gore-Tex.”

Penaflor also had a lighter he used to build a fire, throwing his prey — three squirrels, one snake, two frogs and two lizards — directly on the embers. He said his ammunition, intended for deer, would have shattered a squirrel so he carefully aimed for the head.

“He really is cognitive of salmonella and wanted to make sure they were thoroughly cooked before he ate them,” Gale said. “He said the taste was OK. He told us, ‘I can’t really explain it, but it wasn’t bad. I was just eating.’ ”

He also worried about accidentally starting a forest fire. “He covered the fire with gravel so it wouldn’t start a forest fire, but the embers would still be lit when he woke up,” Gale said. The elder Penaflor had a cut on his chin from his fall, and tried to keep it clean lest it become infected.

Searchers with dogs and in helicopters scanned the wilderness for days before a storm forced them to suspend the effort on Sept. 27. Penaflor had spotted a helicopter and tried to send smoke signals, but the canopy of the tree must have impeded the view, he told his sons.

The search resumed Saturday, when a hunter called the Mendocino sheriff’s dispatcher and reported that a man at the bottom of a canyon was screaming for help. The hunter was with a group of about eight. One of them scrambled down to Penaflor and then summoned the others to help. They used their coats and sticks to make a stretcher and carried him out.

Several hours passed before rescue units arrived “due to the difficult terrain,” according to a sheriff’s office incident report.

“Gene was evaluated medically, and it was determined he should be extracted via helicopter,” the report said.

Gale Penaflor said his father had started yelling for help after spotting the group of hunters. Though he was weak when he was found, he was released from the hospital after only about three hours, Gale said.

“He had been drinking water regularly, his blood pressure was good and they checked out his vitals,” Gale said. “He was in great shape."

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