- Author: Kathy Keatley Garvey
The Western monarch population at overwintering sites in California indicates a 2022 "great breeding season," says Washington State University entomologist David James, who researches migratory monarchs and spearheads a tagging program in the Pacific Northwest.
"After two thousand miles and eight days, I returned to Washington State after surveying Monarch populations at 24 coastal California overwintering sites stretching from Pismo Beach to Bolinas," he related in an email Sunday and earlier posted on his Facebook page, Monarch Butterflies in the Pacific Northwest.
"As detailed previously, I found three tagged Monarchs (Pismo Beach, Cambria, Santa Cruz) that originated in southern Oregon. I also located or learned of three additional tags in Santa Cruz that have not yet been viewed sufficiently well to get details of serial numbers. If you are visiting Lighthouse Field or Natural Bridges in Santa Cruz over the coming weeks, please watch for these!"
"Populations at the overwintering sites I visited ranged from 100 to 24,000 with sites around Pismo, Cayucos and Cambria having the largest numbers. In total, I saw an estimated 107,650 Monarchs at the 24 sites. Comparing my estimates with the Thanksgiving Counts (TGC) made at these sites in 2021 indicates an almost 80% increase. For example, for nine sites in San Luis Obispo County, I estimated a total of 92,810 butterflies last week, compared to 52,212 in the 2021 TGC. Similarly, in the Santa Cruz/San Francisco area my estimate of 34,310 butterflies at nine sites is almost double the 2021 TGC number for these sites (17,556)."
Pismo Beach, Cayucos and Cambria are all located in San Luis Obispo County, a county located along the state's central coast.
The WSU entomologist singled out for special mention the overwintering population in Cambria; longtime monarch advocate Paul Cherubini alerted him to the site. "This new site, which does not appear on the official list of overwintering sites, is home this November to 15,000 butterflies!" James noted.
"Regardless of the final numbers, there is little doubt that the western Monarch had a great breeding season in 2022."
Check out his spectacular images of Danaus plexippus.
2023 International Western Monarch Summit, Open to All
Meanwhile, enthusiasm is building for the 2023 International Western Monarch Summit, set Jan. 20-22 at Pismo Beach, San Luis Obispo. The three-day conference, sponsored by the Western Monarch Advocates (WMA), will include networking, field trips, and meals.
James, a WMA board member, will be among the keynote speakers from four countries. The event, open to all interested persons, is billed as "an exchange of ideas from across the Western States, Tribal Lands, Mexico, Canada and Australia-all with an interest in our western monarch population! Expand your knowledge and make connections with other Monarch enthusiasts, researchers, and conservation organizations."
As they point out, "our migrating Western Monarch Butterflies do not stop at state or international borders; nor should our efforts to restore them."
Yes, indeed. Monarchs know no borders and neither should we.
- Author: Kathy Keatley Garvey
Professor Elizabeth Crone of Tufts University who researches monarchs (as well as bumble bees), drew a standing-room only crowd when she presented a UC Davis Department of Entomology and Nematology seminar on the decline of Western monarchs.
UC Davis professor Neal Williams, a pollination ecologist who researches native bees, praised her "fearless perspective in the use of statistics; I value her insights." Williams has collaborated with her "off and on" for 20 years.
Crone, who just finished a six-month research sabbatical at UC Davis, says her work centers on population ecology, especially of plants and insects, and plant-animal interactions. "Specifically, I am interested in how environmental changes translate to changes in population dynamics: For example, is there a simple, linear matching of changes in resources to abundance of consumers, or do interactions among individuals and species moderate these responses? Much of my research also involves developing novel quantitative approaches to predict long-term dynamics from small scale observations and experiments. Current projects include studies of butterflies, bees, perennial wildflowers, sugar maples, and acorn-granivore interactions."
In her UC Davis seminar, Crone pointed out that the population of Western monarchs, which overwinter along the California coast, dropped from an estimated 4.5 million in the 1980s to less than 30,000 in the winter of 2019.
After the monarchs leave their overwintering sites in February and head inland, "we don't really know where they are in spring," Crone lamented. "There's not a lot of records of where monarchs are in spring. That's why we're trying to draw on citizen scientists to help us find monarch butterflies in the spring."
Crone is a member of a team of researchers, led by Cheryl Schultz, biology professor at Washington State University, who are recruiting the public, aka citizen scientists, to report sightings of monarchs from Feb. 14 through April 22, Earth Day. The project is called the Western Monarch Mystery Challenge.
To participate in the Western Monarch Mystery Challenge:
- If you see a monarch outside of overwintering groves, take a picture! (Don't worry, it can be far away and blurry.)
- Report it to iNaturalist (the app is free) OR email MonarchMystery@wsu.edu and be sure to include date, species and location for both methods
- You will automatically be entered to win a variety of prizes every week you report a sighting.
All data will be added to the Western Monarch Milkweed Mapper, a year-round community science project tracking milkweeds and monarchs in the West.
Crone told the UC Davis crowd that "we need to understand the basic biology throughout the life cycle....So from a conservation perspective, we know that we need to protect and restore overwintering sites on the coast of California...It also helps to improve summer habitat both for its own sake and maybe to mitigate losses. It other places, this includes planting your own pollinator gardens. It includes minimizing ;pesticide use society-wide."
It's not just agriculturists who use pesticides, said Crone, noting that "California tracks pesticide use." She showed a database that indicated 25 percent of the state's total pesticide use is for non-agricultural uses. This includes pesticide applications in parks, roadsides and golf courses, she said. "That doesn't include people who go to Lowe's or Home Depot and pick up a can of insecticide to prevent the aphids from eating their roses. And read the label and it says, 'Why don't you just spray every week so you never see aphids at all?' So we should be very aware that pesticides are everywhere in our landscape, and a lot of us are using them without thinking about them. And anything we can do to minimize pesticides has got to be good for nearly all insects."
From an applied ecology perspective, Crone considers her biggest accomplishment "helping the Fender's blue butterfly move from being listed as endangered to nearly ready for down-listing. From a basic ecology perspective, I figured out the ecological interpretation of variance terms in mixed models as estimates of spatial heterogeneity and environmental stochasticity, and worked out one of the best examples of how mast-seeding species are synchronized by their pollinators."
"It's an exciting time to be an ecologist," Crone said. "Because the puzzle of linking natural history and theoretical ecology to guide conservation is really intellectually interesting, even from an academic perspective. And it also makes me optimistic."
"We did it with Fender's blue butterfly," she told the crowd. "Maybe we can help prevent other insect populations from being at risk of extinction."
To listen to her talk, access this newly uploaded video from ucdavis.edu/media. Access is free.
