Monarch Butterflies Return to California after 2020 historic lows

Screen Shot 2021-10-23 at 6.51.43 AMWho says species can’t come back from the brink?

-October 23,2021-

Migratory western monarchs are being reported at their overwintering sites in coastal California in greater numbers than last year, with hundreds at some sites and thousands at others, giving hope for the struggling population. These reports are particularly welcome after the population reached an all-time low of 1,914 butterflies last year. So says the Portland based Xerces Society.

This year’s official count has not yet begun. That will take place with the help of over 100 community scientists during the 25th annual Western Monarch Thanksgiving Count, beginning on November 13. Yet these early reports signal the possibility of a rebound in numbers—at least compared to last year’s historic low.

On October 16th, 2021, over 1,300 monarchs were counted at the Pacific Grove overwintering site; this site did not have a single monarch butterfly during last year’s count. Pismo State Beach Monarch Butterfly Grove and an adjacent site tallied roughly 8,000 monarchs on October 20th, 2021; last year, these sites hosted less than 300 butterflies.

Additional smaller estimates and observations from volunteers and the public have started to pour in from the Bay Area, Santa Cruz, Monterey, Big Sur, Ventura, Los Angeles and elsewhere, with numbers ranging from a few to dozens to hundreds, of monarchs. Altogether, there appear to be over 10,000 monarchs easily accounted for at the overwintering sites.

The low count of fewer than 2,000 monarchs in 2020 followed two years of record lows of under 30,000 butterflies each year. The number counted last year represents a 99.9% decline from the millions of western monarchs that overwintered in California in the 1980s.

“We are overjoyed that migratory monarch butterflies have not disappeared from the western U.S.,” said Emma Pelton, a senior conservation biologist and western monarch lead for the Xerces Society for Invertebrate Conservation. “These early counts give us hope that, if we all work together, we can still bring western monarchs back.”

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