Monarch population rebounds

This story is a month old at this point, but these days I'll share any good news I can get:

In encouraging news, the eastern monarch butterfly population nearly doubled in 2025, according to a new report announced in Mexico. The population wintering in central Mexico's forests occupied 4.42 acres, up from 2.22 acres during the previous winter. While monarchs occupied nearly twice as much forest habitat as last year, populations remain far below the long-term average.

The survey, Forest Area Occupied by Monarch Butterflies Colonies in Mexico During the 2024-2025 Hibernation Season is conducted annually by WWF-Mexico and Mexico's National Commission of Protected Natural Areas in collaboration with local communities, and it serves as an important indicator of the butterfly's overall population health. 

“We recognize the key role of local communities, as well as the support of the government of Mexico in conserving the forest and providing this iconic species with the opportunity to thrive,” said Jorge Rickards, director general of WWF Mexico. "It’s now time to turn this year’s increase into a lasting trend with an all-hands approach where governments, landowners, conservationists, and citizens continue to safeguard critical habitats along the monarch’s North American migratory route.”

Scientists attribute much of this year’s population growth to better weather conditions in 2024—with less severe drought than in previous years—along the butterflies' migration route from the United States and Canada to Mexico.

Improvements have also been made in protecting the overwintering forests in Mexico from threats such as illegal logging. Here's this year's graph from monarchwatch.org:

monarchwatch.org

One season does not a trend make, and as the graph above shows, the migrating monarch butterfly population is tis just a fraction of what it's historically been. But given last year's particularly grim report, this is good. Monarchs are resilient - how many other species can double their population in the span of a single year? - but they still need our help:

Monarchs still face several threats. For example, climatic variations in the monarch’s breeding areas in Canada and the United States can impact the abundance of milkweed, the only plant in which the butterflies lay their eggs, and from which monarch caterpillars feed. Land-use changes in the United States, combined with the widespread use of herbicides and insecticides, have also contributed to the loss of milkweed and other nectar plants adult monarchs need to feed from. And while high levels of illegal logging in the monarch butterfly reserve have been halted, forest degradation in the overwintering sites in Mexico could be a threat if left unchecked.

Remember, folks: 80% of our agricultural production depends on pollinating insects such as monarchs, and other pollinators are having population crises of their own. Protecting the monarch isn't just good for them; it's good for us.

So plant that milkweed.