- Author: Kathy Keatley Garvey
Monarchs and California golden poppies...Color them orange...Color them bold...Color them beautiful...
And color them natives...
The California golden poppy, Eschscholzia californica, California's state flower, is popping up all over, while monarchs, Danaus plexippus, are winging their way inland from their overwintering sites along the California coast.
The overwintering population in California dropped this year by 30 percent as compared to last year, according to the Xerces Society for Invertebrate Conservation. The stormy weather didn't help.
"The 27th annual Thanksgiving count ran from November 11 through December 3, 2023, totaling 233,394 butterflies across 256 overwintering sites in the western United States," Xerces reports on its website. "This tally is slightly lower than last year's (330,000), yet similar to the 2021 count. The overwintering population of western monarchs remains at approximately 5% of its size in the 1980s."
Overall, habitat loss and increased use of pesticides and herbicides continue to be key factors in the decline of the monarch population.
Interestingly enough, both monarchs and California golden poppies are toxic. "All parts of the (California golden poppy) plant have toxic properties if ingested," according to the State of California Capitol Museum website. And, as we all know, monarchs are toxic. As caterpillars, monarchs sequester or store toxins from milkweed, and those toxins help protect them from predators. The coloring is also a deterrent.
Two natives, toxic, but beautiful...
- Author: Kathy Keatley Garvey
Professor Thorp (1933-2019), a 30-year member of the Department of Entomology and Nematology and a worldwide authority on bees, was a tireless advocate of bumble bee conservation. During his retirement, he co-authored Bumble Bees of North America: An Identification Guide (Princeton University, 2014) and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday, 2014).
And every summer from 2002 to 2018, Thorp volunteered his time and expertise to teach at The Bee Course, an annual workshop sponsored by the American Museum of Natural History and held at the Southwestern Research Station, Portal, Ariz.
Thorp also served as the regional co-chair of the Wild Bee Specialist Group of the International Union for Conservation of Nature (IUCN) and sounded the alarm about bumble bee declines, including Franklin's bumble bee, Bombus franklini, found only in its narrow distribution range of southern Oregon and northern California. Thorp last saw it near Mt. Ashland in 2006 and it is is now feared extinct or at the brink of extinction. The bee inhabits--or did--a 13,300-square-mile area confined to five counties--Siskiyou and Trinity counties in California; and Jackson, Douglas and Josephine counties in Oregon.
Enter the California Bumble Bee Atlas (CBBA), a collaboration of the California Department of Fish and Wildlife (CDFW), Sacramento, and the Xerces Society for Invertebrate Conservation, headquartered in Portland, Ore. Launched in March 2022, the Atlas is a "collaborative community science effort to track and conserve the state's native bumble bee species," according to Dylan Winkler, bumble bee scientific aide for the CDFW's Wildlife Diversity Program.
Back in September 2021, the U.S. Fish and Wildlife Service announced that the American bumble bee, "whose populations have plummeted by nearly 90 percent, may warrant Endangered Species Act protection." The announcement kicked off a one-year status assessment of the species. (See news story)
If you're interested in bumble bee conservation, take note. Winkler will lead a "Bumble Bee Walk" from 10 a.m. to noon on Saturday, May 28 in the UC Davis Arboretum and Public Garden. The goal is to teach interested participants how to survey bumble bees. You can pre-register at https://arcg.is/0PDyO4. Organizers plan to cap attendance at 20 people. Details about this Atlas event and several more scheduled in June:
- Saturday, May 28: UC Davis Arboretum, Davis, CA (Yolo County), parking at Putah Creek Lodge Parking Lot, Garrod Drive, Davis, CA 95616. Tour of the native plant gardens and the forest along Putah Creek from 10 a.m. to noon.
- Saturday, June 4: The Gardens at Lake Merritt, 666 Bellevue Avenue, Oakland, CA (Alameda County). Tour of the gardens from 9 a.m. to 11 a.m.
- Sunday, June 5: College of Marin at Kentfield (Marin County), parking at covered Lots 6/7 off College Ave, Kentfield, CA 94904. Details: Meet at bridge over Corte Madera Creek. Tour of the campus native plants from 10 a.m. to noon.
- Saturday, June 18: Soil Born Farms, Rancho Cordova, CA (Sacramento County), parking at Soil Born Farms: American River Ranch, 2140 Chase Drive, Rancho Cordova, CA 95670. As part of National Pollinator Week, the group will tour the gardens from 10 a.m. to noon. Closed-toed shoes required.
Of the 50 species of bumble bees found in North America, an estimated 25 inhabit California. Overall, a quarter is at risk, according to the Atlas website. The decline is attributed to "loss or fragmentation of habitat, pesticide exposure, climate change, overgrazing, competition with honey bees, low genetic diversity, and perhaps most significant of all, the introduction and distribution of pathogens through commercial honey bee and bumble bee colonies used for crop pollination. All of these factors likely interact, increasing pollinator vulnerability. To support bumble bees, it is critical to protect existing habitat while creating and maintaining new habitat."
Winkler says "we will be using butterfly nets to catch bees, then move them to small vials, and chill them in coolers with ice, so we can take ID'able photographs of them before releasing." The full protocol is at https://www.cabumblebeeatlas.org/point-surveys.html
What bumble bees might you see May 28 in the Arboretum? Bombus vosnesenskii, the yellow-faced bumble bee, and B. melanopygus, the black-tailed bumble bee. "There is a record of B. crotchii at the arboretum from last year around the same date, which is rare and would be amazing to see!" Winkler said.
The project is funded by the U.S. Fish and Wildlife Service through the Wildlife and Sport Fish Restoration Fund. Funding is also provided by the Bureau of Land Management and several private foundations. Read more about the project and the list of coordinators here.
- Author: Kathy Keatley Garvey
Picture this during National Pollinator Week: five monarch caterpillars and assorted honey bees sharing tropical milkweed.
It was love at first bite. Or love at first sip.
The 'cats kept munching and the bees kept foraging. Neither species seemed interested in the other.
But the adult monarchs definitely showed more interest in the tropical milkweed (Asclepias curassavica), a non-native, than the other two species, both natives, that we planted: the narrow leaf (A. fascicularis) and showy milkweed (A. speciosa).
They laid eggs only on the tropical milkweed, and so far, have produced five caterpillars.
The score to date:
Tropical milkweed: 5 caterpillars
Narrow leaf milkweed: 0
Showy milkweed: 0
Reminder: Folks planting the tropical milkweed in temperate zones (like here in Vacaville,Calif.) must remove or cut back the tropical milkweed by winter. "A protozoan parasite of monarch butterflies, Ophryocystis elektroscirrha or OE for short, can travel with monarchs visiting the plants and become deposited on leaves," explains the Xerces Society for Invertebrate Conservation.
Yes, indeed. But meanwhile, we're witnessing untold sharing on the wildly popular tropical milkweed by not only monarch caterpillars but honey bees, syrphid flies, bumble bees, carpenter bees, leafcutter bees and sweat bees.
We gardeners and photographers are also drawn to the spectacular red, orange and yellow flowers that add both beauty and color to a cherished pollinator patch in the midst of the COVID-19 pandemic...and National Pollinator Week.
- Author: Kathy Keatley Garvey
If you've ever wanted to converse with butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, about "butterflies and the apocalypse" and sip a beer (or another beverage) at the bar at the same time, here's your chance.
The Davis Science Café has booked "A Conversation with Arthur Shapiro: Butterflies as Heralds of the Apocalypse" at 5:30 p.m., Wednesday, April 10 in the G Street Wunderbar, located at 228 G St., Davis. The event, hosted by professor Jared Shaw, professor and interim department chair of the UC Davis Department of Chemistry, is free and open to the public (but the refreshments are not).
Shapiro has monitored butterfly population trends on a transect across central California since 1972. The 10 sites stretch from the Sacramento River Delta through the Sacramento Valley and Sierra Nevada mountains to the high desert of the Western Great Basin. The largest and oldest database in North America, it was recently cited by British conservation biologist Chris Thomas in a worldwide study of insect biomass.
What's going on with the butterflies?
The overwintering western population of the monarch butterfly on the central California coast declined 86 percent last winter, the Xerces Society for Invertebrate Conservation indicates on its website. "Working at a conservation nonprofit means that we often come across bad news, but the results from this winter's Western Monarch Thanksgiving Count left us shocked: an all-time record low of 28,429 monarchs at 213 sites. This number is an 86% drop from the previous count done at Thanksgiving 2017, when 192,668 monarchs were counted at 263 sites (comparing only the sites monitored in both years)—and a dizzying 99.4% decline from the numbers present in the 1980s (Schultz et al. 2017). In short, only one of every 160 monarchs present in the 1980s exists today."
At the 2018 Butterfly Summit at Annie's Annuals and Perennials in Richmond, Shapiro told the crowd that "The vast majority of the butterflies we monitor are emerging earlier in the year now than they were in the 1970s."
His research shows that not only are butterflies coming out earlier, but "we also find trends in population and species richness."
Shapiro, a member of the UC Davis faculty since 1971 and author of the book, Field Guide to Butterflies of the San Francisco Bay Area and Sacramento Valley Regions, said that "in a nutshell, at low elevations, butterfly faunas have been declining slowly until 1999. In 1999, 17 species had an abrupt fall in abundance, spontaneously. On its face, this was a non-random event. The decline was then rapid from 1999 to the onset of the recent drought and then things went up again."
Science Café, initially supported by the National Science Foundation, is currently supported by the Department of Chemistry and Division of Mathematical and Physical Sciences and promoted by Capital Science Communicators.
Science Café sessions are hosted the second Wednesday of each month. Topics so far this year? Plant ecologist Mark Schwartz of the UC Davis Department Environmental Sciences and Policy held forth at the March session on "Does California Have a Wildfire Problem? Can It Be Fixed?" The February session featured Professor Roland Faller of the UC Davis Department of Chemical Engineering on "Using Computers to Understand Materials: From Proteins to Semiconductors" while Professor Denis Marcellin-Little of the UC Davis School of Veterinary Medicine's Surgical and Radiological Sciences discussed "Don't Try That at Home; High-End 3D Printing in Orthopedic Surgery" at the January session.
So it's butterflies and the apocalypse on April 10. Ask your questions, sip an adult beverage (or another beverage) and enjoy the evening!
- Author: Kathy Keatley Garvey
You're in luck.
The Xerces Society for Invertebrate Conservation is planning a free field trip on "Cover Cropping for Beneficial Insects" from 9 to 11:30 a.m., Wednesday, March 28 at the Muller Ranch LLC, located at 15810 County Road 95, Woodland. The event is open to the public, but reservations should be made: email Jessa Kay Cruz, Xerces Society's senior pollinator and ag biodiversity specialist at jessa.kay-cruz@xerces.org.
Among those speaking is Yolo County Farm Advisor Rachael Long, an expert on hedgerows and cover crops. See her UC Agriculture and Natural Resources (UC ANR) publication on "Establishing Hedgerows on Farms in California."
Here's the agenda for the field trip:
- 8:30 to 9 a.m.: Arrive and Sign-In
- 9 to 9:20 a.m.: Welcome and Introduction, Project Background
Jessa Kay Cruz, Senior Pollinator and Ag Biodiversity Specialist, The Xerces Society - 9:20 to 9:40 a.m. Cover Cropping for Soil Health
Jeff Borum, Soil Health Coordinator - 9:40 to 10 a.m. Cover Cropping for Beneficial Insects
Rachael Long, Farm Advisor, UC Cooperative Extension - 10 to 10:30 a.m.: Insect Ecology, Plant Species Selection, Implementation and Management
Jessa Kay Cruz, Senior Pollinator and Ag Biodiversity Specialist, The Xerces Society - 10:30 to 10:50 a.m.: A Farmer's Perspective: Why Do It and How Well Does it Work?
Colin Thomas Muller, Muller Ranch LLC - 10:50 to 11:10 a.m.: Accessing Natural Resources Conservation Service (NRCS) Cost-Share Programs and Understanding the Planning Process
Fanny Ye, Soil Conservationist, NRCS, and Corey Shake, Point Blue / NRCS Partner Biologist
Continuing education credits are available.
On the field trip, you're likely to learn about pollinators, predators, pests and parasitoids as well as plants (cover crops). Keep your eyes out for such beneficial insects as lady beetles, aka ladybugs. These predators make short work of aphids, scales and other soft-bodied insects. Keep them close!
