A Memorable Year for the Western Monarchs

It's definitely going to be quite a memorable year for the Western monarch butterflies--memorable as in "record low populations at the overwintering sites along the California coast."

Matthew Shepherd, director of communications and outreach at the Xerces Society for Invertebrate Conservation, announced Nov. 30:  

"We were hoping for better news to share about the state of the monarch population gathered in California to overwinter, but the early numbers from the Western monarch Thanksgiving Count don't paint a good picture. With 74 sites reported -- over 30 percent of the anticipated data -- only 1,224 monarchs have been counted. If this reflects monitoring at the rest of the sites, we may see fewer than 10,000 monarchs overwintering in California this year. This is a significant decline from the low numbers of the last two years where the total hovered just under 30,000 monarchs. These numbers are a tiny fraction of the millions of monarchs that likely visited overwintering sites in the 1980s and the hundreds of thousands of monarchs that graced California's coast as recently as the mid-2010s."

In her blog about the crisis, Xerces Society's endangered species conservation biologist Emma Pelton quoted Scott Black, executive director of the Xerces Society, who lamented that monarch populations may be suffering from “death by a thousand cuts.”

That would be "destruction, degradation and neglect of overwintering sites, climate change, and overuse of insecticides are likely contributing factors," Pelton wrote.

"The most striking thing about the dwindling number of monarchs," Pelton pointed out, "is that this is closely following what models predicted. A 2017 study by Cheryl Schultz, a professor at Washington State University, and coauthors, predicted if the population dropped below 30,000 monarchs—which it did in 2018 and 20019—there was a high probability that it would spiral down further. Unfortunately, we seem to be witnessing that prediction come true."

What can we do?

Pelton, the Xerces Society's western monarch lead who works on the western population of monarch butterflies (including adaptive management of overwintering habitat in California and breeding habitat throughout the western United States) says this:

"Western monarchs need everyone's help today more than ever.  Check out our Western Monarch Call to Action and our This Is How You Can Help handout to learn more about how to support western monarchs during this crucial time. These actions will benefit monarchs and also support our many other native bees and butterflies."

Ironically, in our family's pollinator garden in Vacaville, Calif. (where we grow four species of milkweed and assorted nectar plants) this was the best-ever year for monarchs in over a decade. We collected more than 300 eggs or caterpillars, which we, UC Davis researchers and University of Nevada researchers reared.

A very good year for them in a small pollinator garden, but a very bad year for them at their overwintering sites along the California coast. 

Monarchs need our help.