- Author: Kathy Keatley Garvey
It was a gathering of science experts and policymakers to share science and conservation actions to help the declining western monarch population. The scientists discussed the natural history of the monarch (Danaus plexippus), its population status, habitats and barriers to conservation success.
"It was a great group of folks working hard to connect science and policy to improve monarch conservation," Yang said. "It was a privilege to be a part of it.'
During the summit, the Department of the Interior announced a $1 million award to the National Fish and Wildlife Foundation's (NFWF) Monarch Butterfly and Pollinators Conservation Fund, and the U.S. Fish and Wildlife Service (USFWS) announced a Pollinator Conservation Center.
Sen. Merkley organized the summit in collaboration with the Department of the Interior. Officials attending included Secretary of the Interior Deb Haaland; Sen. Ron Wyden of Oregon; Sen. Alex Padilla of California; Cong. Jimmy Panetta of California; Assistant Secretary for Fish and Wildlife and Parks (USFWS) Shannon Estenoz; and U.S. Fish and Wildlife Service Director Martha Williams.
- Professor Matt Forister, the Trevor J. McMinn Endowed Professor in Biology, Foundation Professor, at the University of Nevada, Reno. He holds a doctorate in ecology (2004) from UC Davis where he studied with major professor Art Shapiro, distinguished professor of evolution and ecology
- Elizabeth Crone, former professor and population ecologist at Tufts University and who will join UC Davis starting this fall as a professor in the Department of Evolution and Ecology
- Sarina Jepsen, director of the Xerces Society's Endangered Species and Aquatic Program, who holds a master's degree (2006) in entomology from UC Davis. She studied with major professor Jay Rosenheim, distinguished professor of entomology.
Others giving scientific presentations were Amanda Barth, Western Monarch and Native Pollinator Working Group; Wendy Caldwell, executive director, Monarch Joint Venture; Ryan Drum, wildlife biologist, USFWS; Wayne Thogmartin, quantitative ecologist, U. S. Geological Survey; Cat Darst, wildlife biologist, USFWS, Cheryl Schultz, professor, Washington State University, Pullman; Sarah Hoyle, pesticide program specialist policy lead, Xerces Society for Invertebrate Conservation; and Francis Villablanca, professor, California Polytechnic State University, San Luis Obispo.
"The Senator convened the Monarch Butterfly Summit to elevate the conservation issues that western monarchs face, and to include policy makers in work sessions to identify solutions," Black noted. "Working closely with the USFWS and Xerces, Senator Merkley ensured that issues like pesticides, the availability of early emerging native milkweeds in the spring breeding areas, loss and degradation of western monarch overwintering sites, and other important issues would be highlighted throughout the meeting. Sarina and Sarah did an amazing job representing Xerces – not only in their talks, but in the working groups."
Black wrote that the event "raised the profile of western monarchs. One participant that came up to me enthusiastically and said, 'This was incredible. I have been working on monarchs for decades and never expected to come to a meeting where three U.S. Senators [Merkley, Padilla-CA, Wyden-OR] a congressperson [Panetta-CA] and the Secretary of Interior [Deb Haaland] come to talk about western monarchs!'"
In a news release, the U.S. Department of Interior noted: "In the 1980s, more than 4.5 million monarchs overwintered along the California Coast. Currently, the western overwintering population has declined by more than 95 percent. In 2020, western monarch numbers dropped to all-time lows when only 1,900 overwintering monarchs were observed. In 2021, biologists and the public alike were greeted with the news that monarch numbers were heading in the right direction with approximately 250,000 monarchs estimated at overwintering groves along the coast of California."
"There is no single cause for the extreme multi-decade drop in the western monarch butterflyoverwintering population numbers," according to the Department of Interior, which aims to play "a central role in how the United States stewards its public lands, increases environmental protections, pursues environmental justice, and honors our nation-to-nation relationship with Tribes.
On July 21, the International Union for Conservation of Nature (IUCN), which works in the field of nature conservation and sustainable use of natural resources, listed the migratory monarch on its Red List of Threatened Species (Endangered). It is not yet listed as endangered by the U.S. Fish and Wildlife Service, but is listed (as of Dec. 15, 2020) as a candidate. (See more on the monarch butterfly on the USFWS website.)
“First, we documented early and late seasonal windows of opportunity in the wild, migratory western monarch population," the UC Davis professor said. "Second, our data suggest that early and late seasonal windows were constrained by different factors. Third, climatic and microclimatic variation had a strong effect on the timing and importance of multiple factors affecting monarch development. Broadly, we hope that this study contributes to a more temporally detailed understanding of the complex factors that contribute to year-to-year variation in monarch breeding success.”
The project, funded by two of Yang's National Science Foundation grants, involved UC Davis, Davis Senior High School and the Center for Land-Based learning. Among them were 107 high school students and a K-12 teacher, 18 UC Davis undergraduate students, three graduate students and two post-graduate researchers.
“This study collected a high-resolution temporal dataset on milkweed-monarch interactions during the last three years prior to the precipitous single-year population decline of western monarchs in 2018," Yang said. He organized and led a 135-member team, all co-authors of the paper, “Different Factors Limit Early- and Late-Season Windows of Opportunity for Monarch Development,” published in the journal Ecology and Evolution. (This document is open access at https://bit.ly/3volFaI.)
Other monarch research from the Yang lab is pending publication. Professor Yang discussed the monarch crisis on Science Friday, National Public Radio, on Feb. 4, 2022. (See 'How Long Will California's Butterfly Boom Last')

