MEXICO CITY — When I met Homero Gómez González last month, he pointed to the hilltop just above him in the town of Rosario, a dense forest where millions of monarch butterflies had recently arrived from the United States after their yearly pilgrimage to central Mexico.

“It’s been a fight to maintain it,” he said. “And it hasn’t been easy.”

He was referring to the decades-old battle against illegal logging in North America’s premier monarch butterfly habitat. Gómez González had been at the forefront of that public fight — against men who still wielded enormous power in Rosario. By the time we met, he thought that he had prevailed — and he spent as much time as he could with the butterflies he had helped save, a thundering, broad-shouldered man in a cloud of orange and black monarchs.

Last week, a month after we had lunch together, Gómez González disappeared. Investigators have not suggested any theories about what might have happened to him, but many in Rosario suspect that loggers kidnapped him.

Gómez González, the manager of Rosario’s butterfly sanctuary, was last seen Jan. 13. On Tuesday, investigators interrogated 53 municipal police officers about his disappearance, according to the attorney general of Michoacán state. A search team using rescue dogs has been dispatched to comb the area. No arrests have been made.

More than 61,000 people are missing in Mexico, authorities announced this month, one of the largest numbers in Latin America. The majority are suspected to be victims of criminal organizations. In Gómez González’s case, as in most, his community has been left to piece together its own narrative of what might have happened to him, however incomplete. For now, no evidence points to any particular suspect.

Gómez González, 50, like many others in Rosario, grew up cutting down the village’s timber and selling it. It was the heart of the local economy. Between 2005 and 2006, 461 hectares in Michoacán were lost to illegal logging. Entire swaths of the forest were razed — including the primary habitat for the butterflies, who fly thousands of miles from the United States and Canada to spend winter there.

When environmentalists, watching the destruction of the population in real time, began lobbying for anti-logging measures, many in Rosario were up in arms — Gómez González included. He had grown up admiring the butterflies — his grandparents told him they carried the souls of their ancestors — but he knew how much Rosario depended on its timber industry.

“We were afraid that if we had to stop logging, it would send us all into poverty,” he told me.

But Gómez González, who would serve as Rosario’s commissioner — the mayor of the small community — eventually came around to the idea that preserving the monarchs would also draw tourism to Rosario, which could be an important revenue stream. Later that preservation was codified into law, first limiting logging in Rosario and then outlawing it entirely. The federal Monarch Butterfly Biosphere Reserve, of which the Rosario sanctuary is a part, is now a UNESCO World Heritage Site.

Gómez González started working alongside the World Wildlife Fund on its conservation initiatives. He created a Twitter account where he posted videos of himself surrounded by butterflies, called their migration “the great spectacle” and invited visitors to Rosario’s monarch sanctuary. He stood still when they landed on his face and clung to his clothes.

“Since he was young, Homero has been behind the sanctuary,” said Gloria Tavera, an official with Mexico’s National Commission of Natural Protected Areas.

But Tavera said she doesn’t think his disappearance was connected to his activism. 

“We think they are independent things,” she said. She did not suggest an alternative theory.

I met Gómez González at the cafeteria in the Rosario sanctuary, where he appeared to know every waiter and janitor and tour guide by name. He walked around with the confidence of a local celebrity.

In the hours before he was last seen, he added more videos of the monarchs to his Twitter feed. Authorities have said little about his disappearance.

“We can’t disregard any possibilities,” said Magdalena Guzmán, the spokeswoman for the Michoacán attorney general’s office. She said Gómez González’s family had recently received calls demanding money for his safe return. They are also being investigated.

The Michoacán state Human Rights State Commission thinks illegal loggers could be responsible.

“We can’t ignore the work of this man, who was considered an activist attempting to preserve the forest of the monarch,” said Mayte Cardona, a member of the commission. 

Siobhán O’Grady in Washington and Gabriela Martínez contributed to this report.