Quantcast

Monarch Butterfly Population Plummets in California

Animals
Monarch butterfly on swamp milkweed. Jim Hudgins / USFWS

The population of monarch butterflies that spend winter along the California coast dropped 86 percent since 2017, according to a recent count by the Xerces Society, an invertebrate conservation group.

Preliminary results from the Western Monarch Thanksgiving Count, an annual citizen science program, recorded less than 30,000 butterflies overwintering in California, a significant decline from the estimated 192,000 in 2017. The official numbers will be released later this month.


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 ( Schultz et al. 2017), 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 is not yet clear why their numbers were so low in 2018, although prolonged drought, a late rainy season, as well as smoke and poor air quality caused by the region's devastating wildfires could be to blame, Pelton suggested.

The latest count adds to more bad news for the iconic species, whose numbers have precipitously declined.

"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, noting that one study estimated 4.5 million monarchs overwintering in California in the 1980s.

"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 risk 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 reduced milkweed, a native wildflower and main food source for monarch caterpillars and the only plant on which adult monarchs lay their eggs.

Despite the grim report, there are ways you can help the survival of the beloved species, which are also crucial pollinators for many different kinds of wildflowers.

"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.

Learn more about how you can help.

EcoWatch Daily Newsletter

Micromobility is the future of transportation in cities, but cities and investors need to plan ahead to avoid challenges. Jonny Kennaugh / Unsplash

By Carlo Ratti, Ida Auken

On the window of a bike shop in Copenhagen, a sign reads: Your next car is a bike.

Read More Show Less
An American flag waves in the wind at the Phillip Burton Federal Building in San Francisco, California on May 17 where a trial against Monsanto took place. Alva and Alberta Pilliod, were awarded more than $2 billion in damages in their lawsuit against Monsanto, though the judge in the case lowered the damage award to $87 million. JOSH EDELSON / AFP / Getty Images

By Carey Gillam

For the last five years, Chris Stevick has helped his wife Elaine in her battle against a vicious type of cancer that the couple believes was caused by Elaine's repeated use of Monsanto's Roundup herbicide around a California property the couple owned. Now the roles are reversed as Elaine must help Chris face his own cancer.

Read More Show Less
Sponsored
Butterfly habitats have fallen 77 percent in the last 50 years. Pixabay / Pexels

The last 50 years have been brutal for wildlife. Animals have lost their habitats and seen their numbers plummet. Now a new report from a British conservation group warns that habitat destruction and increased pesticide use has on a trajectory for an "insect apocalypse," which will have dire consequences for humans and all life on Earth, as The Guardian reported.

Read More Show Less
Six of the nineteen wind turbines which were installed on Frodsham Marsh, near the coal-powered Fiddler's Ferry power station, in Helsby, England on Feb. 7, 2017.

Sales of electric cars are surging and the world is generating more and more power from renewable sources, but it is not enough to cut greenhouse gas emissions and to stop the global climate crisis, according to a new report from the International Energy Agency (IEA).

Read More Show Less
"Globally, we're starting to see examples of retailers moving away from plastics and throwaway packaging, but not at the urgency and scale needed to address this crisis." Greenpeace

By Jake Johnson

A Greenpeace report released Tuesday uses a hypothetical "Smart Supermarket" that has done away with environmentally damaging single-use plastics to outline a possible future in which the world's oceans and communities are free of bags, bottles, packaging and other harmful plastic pollutants.

Read More Show Less
Sponsored
Children are forced to wear masks due to the toxic smoke from peat land fires in Indonesia. Aulia Erlangga / CIFOR

By Irene Banos Ruiz

Pediatricians in New Delhi, India, say children's lungs are no longer pink, but black.

Our warming planet is already impacting the health of the world's children and will shape the future of an entire generation if we fail to limit global warming to well below 2 degrees Celsius (35.6°F), the 2019 Lancet Countdown Report on health and climate change shows.

Read More Show Less
Private homes surround a 20 inch gas liquids pipeline which is part of the Mariner East II project on Oct. 5, 2017 in Marchwood, Penn. Robert Nickelsberg / Getty Images

The FBI is looking into how the state of Pennsylvania granted permits for a controversial natural gas pipeline as part of a corruption investigation, the AP reports.

Read More Show Less
Three cows who were washed off their North Carolina island by Hurricane Dorian have been found alive after swimming at least two miles. Carolina Wild Ones / Facebook

Three cows who were washed off their North Carolina island by Hurricane Dorian have been found alive after swimming at least two miles, The New York Times reported Wednesday.

Read More Show Less