Going up into the Monarch Butterfly Biosphere Reserve, between the Mexican states of Michoacán and Estado de México at an altitude of almost 10,000 feet, can be dizzying. The flashes of orange catch the corner of your eye, dart around your shoulders and streak above in the sky. Neon in your face, rustling your hair and eyelashes, as you realize you are surrounded.

Butterflies crowd the horizon, litter the walking path and tremble on the green leaves of the trees in which they nest. They circle and smash into visitors, who are encouraged to stay as quiet as possible so as not to disturb the fragile insects.

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Credit…Katie Orlinsky for The New York Times

Every November, the reserve begins to welcome hundreds of millions of monarch butterflies, which journey several thousand miles from the United States and Canada to escape the coldest months of the year. But the monarchs, and their spectacular migration, are at risk of becoming extinct from rising temperatures and drought caused by climate change; loss of habitat and the eradication of milkweed, the plants that nourish and host their eggs; and toxic pesticides.

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Credit…Katie Orlinsky for The New York Times
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Credit…Katie Orlinsky for The New York Times

The reserve has felt, to the conservationists and guides working there, like a sanctuary both for the butterflies and for surrounding communities; despite Michoacán’s being one of the most violent states in the country because of organized crime cartels, residents of towns overlapping the reserve said they had generally felt safe.

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Credit…Katie Orlinsky for The New York Times
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Credit…Katie Orlinsky for The New York Times

But the illusion of peace has been shattered. This year, Raúl Hernández Romero, a sanctuary guide, and Homero Gómez González, a local politician and manager at the reserve, were found dead within weeks of each other. The men were devoted to the protection of the monarchs.

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Credit…Katie Orlinsky for The New York Times
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Credit…Katie Orlinsky for The New York Times

Environmental defenders in Mexico, and elsewhere in Latin America, are increasingly under threat or attack from criminal groups, particularly when they get in the way of the groups’ commercial interests in logging and farming.

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Credit…Katie Orlinsky for The New York Times
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Credit…Katie Orlinsky for The New York Times

According to the Mexican Environmental Law Center, 21 environmental activists were murdered in 2018; a separate review by the Mexican human-rights group “All Rights for All” found that another 21 were killed last year. The murders have illuminated the burden mostly Indigenous, poor communities carry to conserve their environments.

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Credit…Katie Orlinsky for The New York Times

Much of the butterfly reserve is split into several sections, each managed by a community called an ejido, a Mexican form of collective land management.

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Credit…Katie Orlinsky for The New York Times

“What we are interested in is taking care of ourselves — being autonomous,” said Paulino Guzmán González, a guide at El Rosario Monarch Butterfly Sanctuary, one of the sections, said. El Rosario is an ejido of about 1,000 people in the Michoacán highlands. Members work as guides and in other jobs at the sanctuary.

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Credit…Katie Orlinsky for The New York Times

Once the butterfly migration and the influx of tourists — up to 150,000 in a season — end, residents do reforestation work for the government for about 200 pesos, or $8, a day, and occasional, equally low-paid work in state-approved logging. More often than not, they migrate to Mexico City or the United States for jobs.

The Mexican government and international organizations like the World Wildlife Fund support and put pressure on the ejidos to protect their habitat, and residents willingly do the work, planting trees and tending to diseased older ones. As a member of the ejido said, “We need the forest to survive.”

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Credit…Katie Orlinsky for The New York Times

Alexis Okeowo (@alexis_ok) is a staff writer at The New Yorker. Katie Orlinsky (@KatieOrlinsky) is a freelance photographer.

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