Monarch butterflies blanketed 2.93 hectares of oyamel fir forest in central Mexico this winter — their largest footprint in seven years, and a 64% jump from the 1.79 hectares recorded in the 2024–25 season.

The figures, released this week by WWF Mexico, mark a genuine bright spot. A less punishing spring and summer across the United States meant more eggs and larvae survived the breeding season, and reduced drought along the southbound migration corridor helped adults reach their wintering grounds in better shape.

But the numbers need context. At their peak in the mid-1990s, monarchs carpeted more than 18 hectares of Mexican forest. Today’s 2.93 hectares represents a decline of more than 80% from that baseline. Scientists estimate that 6 hectares — roughly double the current figure — is the minimum threshold needed to keep the eastern migratory population above extinction risk. A federal status assessment has put the eastern monarch’s chance of extinction within 60 years as high as 74%.

The western monarch population, meanwhile, offers no such consolation: fewer than 12,260 butterflies were counted this winter, the third-lowest figure on record and a decline exceeding 95% since the 1980s.

The threats haven’t changed. Glyphosate-driven milkweed loss across the U.S. Midwest, neonicotinoid exposure, climate disruption to winter habitat, and illegal forest clearing for avocado cultivation in Mexico all continue to press the species. As Tierra Curry of the Center for Biological Diversity put it, monarchs still need help — and we still need monarchs.

A good winter doesn’t erase a 30-year decline. But it does prove the population can rebound when conditions allow, which is the best argument conservationists have for protecting the conditions that matter.

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