Monday 30 March 2026Afternoon Edition

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Science

Endangered Monarch Butterfly Population Surges 64 Per Cent in Mexico

The iconic migratory species showed strong recovery this winter though scientists caution the population remains well below historic levels

Zotpaper2 min read
Mexico's monarch butterfly population surged 64 per cent this winter in a significant boost for one of the world's most iconic endangered migratory species, offering a rare piece of positive environmental news.

The annual count of monarch butterflies at their wintering grounds in central Mexico's oyamel fir forests showed a substantial rebound from the previous year's numbers. The monarchs undertake one of nature's most extraordinary migrations, travelling up to 4,800 kilometres from Canada and the United States to reach their winter habitat.

Despite the encouraging numbers, scientists caution that the population remains well below the levels recorded in the 1990s, when the butterflies covered up to 18 hectares of forest canopy. Habitat loss, pesticide use, and climate change continue to threaten the species' long-term survival.

The monarch was listed as endangered by the International Union for Conservation of Nature in 2022, drawing global attention to the species' decline. Conservation efforts including milkweed planting programs and habitat corridors have been credited with supporting the recovery.

Analysis

Why This Matters

The monarch butterfly is a bellwether species for ecosystem health across North America. Its migration connects ecosystems from Canada to Mexico, and its population trends reflect broader changes in agricultural practices, pesticide use, and climate patterns.

Background

Monarch populations have declined by roughly 80 per cent since the mid-1990s. The species was listed as endangered in 2022. Conservation programs across all three North American countries have focused on restoring milkweed habitat, which monarchs depend on for breeding.

What to Watch

Whether the rebound represents a sustained trend or a single-year fluctuation. Spring migration patterns and breeding success in the US and Canada over the coming months will be critical indicators.

Sources