The magnificent Monarch butterfly may become just a memory soon. A story on Eco Watch reports that the population of monarch butterflies that winter along the California coast dropped 86 percent since 2017, according to a recent count by the Xerces Society, an invertebrate conservation group.
Official numbers will be released later this month, but preliminary results from the Western Monarch Thanksgiving Count, an annual citizen science program, recorded less than 30,000 butterflies overwintering in California. That is a significant decline from the estimated 192,000 that were counted in 2017.
Emma Pelton, a Xerces Society endangered species conservation biologist, wrote in a blog post that the initial results are "disturbingly low" and perhaps "catastrophic."
"While overwintering populations naturally fluctuate, even by double digit percentages, the magnitude of this year's drop is of significant concern because the monarch population was already at a new low after the 97 percent decline it has experienced since the 1980s, leading to a situation which may be catastrophic for the western population," Pelton wrote.
The 30,000 butterflies counted is the average quasi-extinction population size — or "the number of adult butterflies needed to ensure persistence of the western monarch population," Pelton explained.
It’s not yet clear why their 2018 numbers were so low. Prolonged drought, a late rainy season, as well as smoke from last year’s wildfires could be to blame, Pelton suggested.
This low count is more bad news for the iconic species, whose numbers have been precipitously declining for decades.
One study estimated 4.5 million monarchs overwintering in California in the 1980s. "In my lifetime, the monarch population in California has gone from millions of butterflies to hundreds of thousands and now, possibly, mere tens of thousands," Pelton wrote.
"Next year will be a real test in how resilient the western monarch population is, after its California overwintering population has been reduced to less than 0.5 percent of its historical size," she added.
Scientists warn that the black-and-orange butterflies — known for their annual, 3,000-mile migration from the U.S. and Canada to Mexico — is at the brink of extinction. Overall, the monarch population has dropped by more than 80 percent over the past two decades.
Their disappearance has been linked to climate change, habitat loss, pesticides and a reduced amount of milkweed, a native wildflower and main food source for monarch caterpillars and the only plant on which adult monarchs will lay their eggs.
There are ways you can help the survival of the beloved species, which is also a crucial pollinator for many different kinds of wildflowers, despite this grim report. Planting milkweed gardens and reducing or eliminating the use of pesticides are two things we can do.
"While western monarchs are facing unprecedented challenges right now, there is still hope that we can recover the population if we work quickly, strategically and together," Pelton said.