Monarch butterfly population plummets at Pismo Beach grove: ‘These numbers are so bad’
Preliminary numbers from an annual monarch butterfly population count in Pismo Beach show the insect species has suffered a devastating blow and is teetering closer to extinction.
Volunteers only saw about 200 butterflies during this year’s count at the Pismo State Beach Monarch Butterfly Grove, one of California’s paramount overwintering site for western monarch butterflies, according to Emma Pelton, senior conservation biologist with the Xerces Society for Invertebrate Conservation.
The nonprofit organization conducts research on the species and leads an annual count, held Nov. 14 through Dec. 6 in 2020.
In 2019, the Pismo Beach grove had more than 6,700 monarchs — 23% of the western monarch population that year — and just five years ago, the site counted about 28,000 butterflies, according to the Xerces Society.
“We might be witnessing the collapse of the species,” Pelton said.
Monarch butterflies see sharp population decline in California
The numbers are low across the state, with the greatest number of monarchs — 550 butterflies, as of Nov. 30 — counted at Natural Bridges State Beach in Santa Cruz, according to a news release by the Xerces Society. That site saw nearly 2,000 butterflies last year.
As of Nov. 30, with about 30% of the data gathered from monarch overwintering sites around California, only 1,224 monarch butterflies were reported in the entire state, according to the Xerces Society.
California may see fewer than 10,000 total monarchs overwintering this year, the Xerces Society wrote in the release.
The final numbers from the annual Xerces Society count are expected to come in late January.
In 2019, the state had about 29,400 monarch butterflies counted in overwintering sites. Five years ago, the state reported nearly 293,000 monarchs in overwintering sites, according to the Xerces Society.
What caused numbers to decline?
The sharp population decline is likely due to a myriad of factors, the nonprofit said.
Severe wildfires, changing temperatures, increased pesticide use and unusually high number of reports of non-migrating monarchs raised in captivity may all impact the butterfly species’ overwintering populations in California, according to the Xerces Society.
It is currently unclear whether the removal of several large eucalyptus trees across Highway 1 from the Pismo Beach grove in October had any detrimental impact on the butterfly population there, Pelton said.
A private landowner cut down the trees on their property because of the massive amounts of bird fecal matter dropped on an adjacent apartment complex, according to Ron Rinell of Bunyon Bros. Tree Service, the company contracted to do the work.
The city of Grover Beach had proposed topping or trimming more than a dozen trees in the same area. But after conservationists expressed concern about the proposal, the city suspended any tree trimming plans until after the overwintering season ends next spring, Grover Beach city manager Matthew Bronson wrote in an email to The Tribune.
Grover Beach is also still working with the California Coastal Commission to investigate the tree removal on the private property and how it occurred without proper approval, Bronson wrote.
It’s currently unclear whether the tree removal caused fewer monarch butterflies to come to the Pismo Beach overwintering site, Pelton said. But the decrease in the species’ population is an obvious trend across the state of California, she added.
“These numbers are so bad that people are just going to give up on saving the species,” Pelton said. “But there’s still reason to believe that they can bounce back, and that we can still save them.”
Insects could get Endangered Species Act protection
Western monarch butterflies are up for protection under the Endangered Species Act.
If granted, the species would have federal protection that would prevent any future habitat destruction without a permit, and a plan to help the butterflies recover would be implemented. In addition, the state of California would receive federal funding to help conserve the species.
An announcement from the U.S. Fish & Wildlife Service on its decision whether to grant the monarchs Endangered Species Act protection is scheduled to come next week, Pelton said.
Though the monarch butterfly is designated as imperiled and vulnerable by the California Department of Fish and Wildlife, receiving federal protection status would boost efforts to save the species.
A judge in the Superior Court of Sacramento County ruled in November that the state of California does not have the legal authority to protect insects under the California Endangered Species Act. This means that the monarchs cannot be protected under the state Endangered Species Act.
“If this ruling stands, the California Endangered Species Act will effectively exclude a huge proportion of animal diversity from a law that was enacted to broadly protect the state’s wildlife,” Sarina Jepsen, the Xerces Society’s director of endangered species, wrote in the nonprofit’s blog. “Pollinators, among other insects, are essential to life on this planet, and should be conserved in their own right — but also for the services that they provide.”
This story was originally published December 8, 2020 at 11:00 AM.
