- Author: Kathy Keatley Garvey
If you traveled to the Natural Bridges State Park in Santa Cruz this fall or to any of the other overwintering monarch sites along coastal California to see these iconic butterflies, did you see very many?
Probably not.
The Xerces Society of Invertebrate Conservation today announced "disturbingly low numbers" of monarch butterflies sightings.
"The Western Monarch Thanksgiving Count (WMTC) has been done annually for the last two decades," wrote Matthew Shepherd, director of communications and outreach. "We're still completing the count for this year, but preliminary results show disturbingly low numbers of monarch butterflies overwintering in California."
"The count results that we have from 97 sites show only 20,456 monarchs. In case you're thinking--'Wait, why say anything now before you have all the data?'--it's worth noting that the sites already reported include many of the most important overwintering groves and combined host the majority of monarchs overwintering in California. In 2017, these sites hosted approximately 148,000 butterflies, more than three quarters of the total monarch overwintering population. The 2018 numbers represents an 86% decline from last year—which was already a low population year."
"We were not expecting this to be a great year because we knew it had been a rough season in the breeding and migratory range, but it's looking worse than anyone had expected," Shepherd related. "If the rest of the Thanksgiving Count data show the same trend as these sites, we anticipate seeing less than 30,000 butterflies overwintering in California this winter. In comparison, last year there were more than 192,000 butterflies counted; in 1997, it was estimated that more than 1 million overwintered; and research suggest that there were at least 4.5 million monarchs overwintering in California in the 1980s."
To read more about the count and what may be causing this abrupt decline in numbers, access the Xerces blog, Early Thanksgiving Counts Show a Critically Low Monarch Population in California.
The Facebook page, Monarch Butterflies in the Pacific Northwest, affiliated with the migratory monarch research projects of Washington State University entomologist David James, knows the situation well.
On Nov. 27, the administrators posted: "This time last year we had found almost 50 of our PNW-tagged Monarchs in California! This year is a very different story with just 10 tag recoveries so far in California. The tenth recovery occurred on November 19 at the Moran Lake overwintering site in Santa Cruz. E5363 was spotted and photographed by John Dayton. This male was reared by Belinda Vos and released in Talent, Oregon on August 17 into extremely smoky skies. Regardless, E5363 flew 367 miles across the landscape to get to Santa Cruz."
And on Nov. 19, the PNW administrators posted:
"Good survival of our small overwintering populations is even more important this year, if we are to see a rebound in numbers next breeding season. However, we may get a boost from the eastern US population which unlike the west had an excellent breeding season in 2018. Back in 1994, the western Monarch population crashed to 'nothingness' then bounced back the next year. The late and revered Monarch researcher, Lincoln Brower connected this remarkable recovery with a likely westward shift of spring migrating Monarchs from the Mexican overwintering sites. He theorized that the western population may be subject to periodic declines from drought and climate cycles and depends on refreshment from Mexico. We will get the opportunity to see if this occurs in spring 2019. If the large summer population of monarchs in the eastern US translates into a large overwintering population, any 'leakage' to west of the Rockies could be significant. Let's keep our fingers crossed!"
And the U.S. Fish and Wildlife Service posted this on its Facebook page yesterday: "The California overwintering monarch population has been reduced to less than 0.5% of its historical size and has declined by 86% compared to 2017."
Want to help them? Here are a few things you can do, according to the U.S. Fish and Wildlife Service:
- Observe and report monarch sightings: https://www.monarchmilkweedmapper.org/
- Plant nectar resources and native plants
- Reduce pesticide use
Meanwhile, brace yourself for a dreary monarch season next year.


- Author: Kathy Keatley Garvey
Is the overwintering monarch butterfly population along California's coast increasing or decreasing?
"So far, far the picture is rather mixed for the number of monarchs in California," according to Matthew Shepherd, communications director for the Xerces Society for Invertebrate Conservation. "More than 130 sites have been surveyed," he told us today. "Northern sites have more butterflies that last year, other sites fewer, and there are many southern sites that haven't yet reported data. A full analysis will be available in January."
The western monarchs, that is those that west of the Rockies, migrate to the California coast to overwinter while the eastern monarchs head to the mountains of central Mexico.
In a news release issued today from its headquarters in Portland, Ore., the Xerces Society said that early data from its Western Monarch Thanksgiving Count suggests "a small increase in butterfly numbers in some parts of the overwintering range."
That is, 2015 may have "been a better year for the beleaguered monarch butterfly in the western United States."
"The overall population size is still far lower than it was in the 1990s, when more than one million butterflies were counted," the news release said. "The surveys indicate that sites north of Santa Cruz are hosting more butterflies than previous years, whereas sites in Monterey, San Luis Obispo, and Santa Barbara counties are reporting fewer numbers of butterflies on average. Several new sites have been reported, including some from Marin County with up to 10,000 monarchs. The data is not yet available for Santa Cruz County and southern California."
The Xerces Society launched its Western Monarch Thanksgiving Count in 1997. This year some 85 volunteers surveyed more than 130 sites over a three-week period centered around Thanksgiving.
We'll all have to wait until January to see the final tallies.
Meanwhile, we were happy to see monarchs roosting in November in the Berkeley Aquatic Park (for the first year ever) and on Mare Island, Vallejo, (maybe also first?) but those clusters may be temporary. As butterfly guru Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, says--they may move on as soon as the weather turns foul.
Maybe they're on their way to Santa Cruz?
"There are some sites where monarchs gather in fall, almost like staging posts in preparation for moving to overwintering locations," Shepherd told us.
Be sure to read the Xerces Society blog by Sarina Jepson, endangered species program director of the Xerces Society, and the news release issued by Xerces Society.
Where can you observe the overwintering monarchs in California? The Xerces Society has kindly provided a web page with links to overerwintering sites in Alameda, Santa Cruz, Monterey, San Luis Obispo and Santa Barbara counties.


- Author: Kathy Keatley Garvey
And that it is. It's designed to alert people to a problem that needs fixing.
And that's good news for the monarch butterflies.
California Gov. Jerry Brown has just signed Assembly Bill 559, which gives authority to the Department of Fish and Wildlife to take actions to conserve monarch butterflies and their habit in California.
“In recent years California has seen a drastic decrease in the Monarch Butterfly population partly due to climate change," said Assemblywoman Patty López (D-San Fernando), author of the bill.
"Conserving this butterfly will have positive impacts on the environment and overall economy for tourism to continue to flourish in cities that the butterfly migrates to,” she said in a news release. "For decades these majestic creatures have called our state home and are an inspiring symbol to many of our communities because of its yearly migration.”
López noted--and correctly so--that monarch butterflies "have been on the verge of being endangered" in their natural habitat (the caterpillars feed only on milkweed) and that their food source has "slowly diminished in the state due to climate change and the use of herbicide among other factors."
The federal government, she said, "committed to conserve the butterfly by expanding public-private partnerships with state and local governments."
The bill is a big step toward California's commitment.
The Xerces Society for Invertebrate Conservation, headquartered in Portland, Ore., helped develop the bill. "The significant thing about this bill is that it clarifies that the California state agency charged with wildlife conservation should, in fact, be working on the conservation of monarch butterflies," said Xerces communication director Matthew Shepherd. "This may not seem a big step, but until now, because of the way that the California state endangered species act was written with respect to invertebrates, it has been unclear whether or not California Department of Fish and Wildlife actually had the authority to work on monarchs. Now they, which allows the department to invest resources and staff time on monarch conservation."
Indeed, saving the monarchs begins with you and me. Get free milkweed seeds (Google "free milkweed seeds" or plant milkweeds obtained from local nurseries.
And why not forgo or cut back on Halloween candy and instead hand out milkweed seeds to the trick or treaters?
Now that's a real treat for monarchs!


- Author: Kathy Keatley Garvey
And when you do, you'll be helping the bees, butterflies, beetles and bats.
In June, the National Pollinator Garden Network launched the Million Pollinator Garden Challenge, hoping to register one million pollinator gardens throughout the country within a two-year period.
The gardens? They can be public or private gardens or landscapes that support pollinators. If you don't have access to a garden, you can fill pots with pollinator plants and grace your deck, patio, balcony or windowsill.
The Porland, Oregon-based Xerces Society for Invertebrate Conservation, an international nonprofit organization that protects wildlife through the conservation of invertebrates and their habitat, is a partner. Communications director Matthew Shepherd wrote a blog last June challenging us all to help the pollinators. The Garden Network, coordinated by the National Wildlife Federation, is an outgrowth of the White House's National Pollinator Strategy. "It draws together nearly two dozen nonprofits and organizations with a shared aim, to make gardens better for pollinators nationwide," Shepherd says.
Your garden should offer a diversity of plants rich in nectar and pollen. No pesticides. That bears repeating. No pesticides. And don't mulch your entire garden; leave some bare soil for solitary bees to nest. And it's good to install bee condos for leafcutter bees and blue orchard bees.
You can register your garden on the SHARE website where "visitors will be able to visually track the progress of the campaign," according to the Million Pollinator Garden Challenge. "Registrants can upload photos and videos of their sites, and the map can be sorted by garden type. In addition, a metric to assess pollinator garden actions across multiple organizations will be in effect as the campaign progresses."
What's in Matthew Shepherd's garden in Beaverton, Ore.?
- Apple
- Bee balm
- Black-eyed Susans
- Blanket flower
- Bleeding heart
- Bugle
- California fuchsia
- Columbine
- Cranesbill
- English lavender
- False indigo
- Foxgloves
- French lavender
- Giant hyssop
- Grape hyacinth
- Great northern aster
- Helebore
- Jerusalem artichoke
- Lamb's ear
- Narrow-leaf coreopsis
- New England aster
- Oregon grape
- Pear
- Phlox
- Plains coreopsis
- Prairie coneflower
- Purple coneflower
- Raspberry
- Rhododendron
- Riddell's goldenrod
- Rosemary
- Salvia
- Showy milkweed
- Snowberry
- Tradescantia
- Wood rose
- Wood strawberry violets
"The front is sunny, the back a shady forest edge—part of the reason for the diversity of plants," Shepherd noted.
In our bee/butterfly garden in Vacaville, Calif., we've planted milkweeds (host plant of the Monarchs), passionflower vine (host plant of the Gulf Fritillaries), English lavender, salvias, blue beard, catmint, lantana, Mexican sunflowers (Tithonia), Photinia, butterfly bushes, honeysuckle, blanket flower, California poppies, alyssum, gaura, California fuchsia, crape myrtle, African blue basil, cherry laurels, foxgloves, sedum, dwarf bulbine, oregano, rock purslane, cosmos, zinnias, tomatoes, cucumbers, pomegranates, olives, lemons and tangerines, to name a few.
We're feeding the bees, butterflies and beetles. And other pollinators, such as hummingbirds and moths. We're not feeding the praying mantids. They're feeding themselves.





- Author: Kathy Keatley Garvey
All winter long my bee condo housed 16 tenants...and one earwig.
And quite comfortably, too, thank you.
It all began last fall when the leafcutting bees laid their eggs, provisioned each nest with a nectar/pollen ball, and plugged it with leaves.
Just about every morning, I did a bed check. Yes, 16 tenants and one earwig. (In actuality, there were probably more of those nasty little earwigs, but each time I checked, I found only one. But lots of frass!)
Bee condos are really just wood blocks drilled with tiny holes for native bee nests.
In late April and early May, the tenants began to stir. As of yesterday, 13 holes had popped open. Ah, emergence! The nocturnal earwig? Nowhere in sight.
You, too, can rear leafcutting bees (Megachile spp.) in your yard. All you need is the housing, which you can buy at most beekeeping supply stores or online. You can also go online and buy the plans to build them.
Senior conservation associate Matthew Shepherd of The Xerces Society for Invertebrate Conservation, in his fact sheet about native bee nesting sites, wrote: "There are 4,000 species of native bees in North America. Together they form the most important group of pollinators. Like all wildlife they are affected by changes in our landscapes, especially the loss of nesting sites. Bees make nests in which they create and provision brood cells for their offspring. In many modern landscapes, a desire for neatness has usually resulted in the removal of bare ground, dead trees, and untidy corners of rough grass—all important nesting sites for bees."
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis, has provided a list of resources for native bee nesting requirements. It's available free on the Harry H. Laidlaw Jr. Honey Bee Research Facility website.
And, the Xerces Society recently published a Pollinator Conservation Handbook where you can find more information about our pollinators.
Just don't expect all your tenants to be pollinators, and all your pollinators to be tenants.

