A Sept. 7 article in Reuters, headlined "Monarchs in Western United States Risk Extinction, Scientists Say," indicated that "Monarch butterflies west of the Rocky Mountains are teetering on the edge of extinction, with the number wintering in California down more than 90 percent from the 1980s, researchers said in a study published on Thursday."
Reuters' reporter Laura Zuckerman wrote that "The migratory monarchs of the western United States have a 63 percent chance of extinction in 20 years and an 84 percent chance in 50 years if current trends continue, according to the study."
The scientists, led by Washington State University conservation biologist Cheryl Schultz, published their work in the journal Biological Conservation. It was funded by the U.S. Fish and Wildlife Service, which is weighing the prospect of offering federal protection for monarch butterflies through the Endangered Species Act. The Xerces Society for Invertebrate Conservation is among those spearheading the effort.
Noted lepidopterist Arthur Shapiro, UC Davis distinguished professor of evolution and ecology who has studied butterflies, including the monarchs, for more than four decades, doubts that the western monarchs are teetering on the edge of extinction.
Shapiro, who maintains a website, Art's Butterfly World. says that yes, the western monarchs have been declining faster than the eastern monarchs, as per the Biological Conservation paper. However, during the drought, California populations appeared to rebound significantly, and it is not known whether the trend will persist, he says.
Their comprehensive and well-researched work, titled "Understanding a Migratory Species in a Changing World: Climatic Effects and Demographic Declines in the Western Monarch Revealed by Four Decades of Intensive Monitoring," was funded in part by the National Science Foundation. Their Oecologia abstract: "Migratory animals pose unique challenges for conservation biologists, and we have much to learn about how migratory species respond to drivers of global change. Research has cast doubt on the stability of the eastern monarch butterfly (Danaus plexippus) population in North America, but the western monarchs have not been as intensively examined. Using a Bayesia hierarchial model, sightings of western monarchs over approximately 40 years were investigated using summer flight records from ten sites along an elevational transect in Northern California."
"Multiple weather variable were examined, including local and regional temperature and precipitation. Population trends from the ten focal sites and a subset of western overwintering sites were compared to summer and overwintering data from the eastern migration. Records showed western overwintering grounds and western breeding grounds had negative trends over time, with declines concentrated early in the breeding season, which were potentially more severe than in the eastern population."
"Temporal variation in the western monarch also appears to be largely independent of (uncorrelated with) the dynamics in the east. For our focal sits, warmer temperatures had positive effect during spring. These climatic associations add to our understanding of biotic-abiotic interactions in a migratory butterfly, but shifting climatic conditions do not explain the overall, long-term, negative population trajectory observed in our data."
In acknowledgments, Shapiro and his colleagues thanked the Xerces Society for Invertebrate Conservation and the North American Butterfly Association for the monarch counts and making the data publicly available.
Meanwhile, since late August, the western monarchs (Arizona, California, Nevada, Oregon, Washington, Idaho and Utah) have been winging their way to their overwintering spots to forested groves along coastal California.
And then, around February, they will head inland to start the process again.
It's an amazing phenomenon.
As I write this, four monarchs are gathering some flight fuel, nectaring from two M's: milkweed and Mexican sunflower in our little pollinator garden in Vacaville, Calif., part of their migratory path to the coast. They flutter from flower to flower, seemingly unaware of the California scrub jay circling them and a photographer zeroing in on them. Or the rain about to fall.
And they did.
But this event wasn't "winged"; it was well planned and rooted in educational information.
Wings? A reference to the flutter of the ever decreasing butterfly wings. The occasion? The inaugural "Wing It" Butterfly Summit, held last Saturday, March 25 at Annie's Annuals and Perennials in Richmond.
A panel of butterfly experts fielded questions focused on "What can we do to help the declining monarch population, as well as other struggling butterfly populations?" Among the speakers were Mia Monroe of the Xerces Society of Invertebrate Conservation, Tora Rocha of the Pollinator Posse and Suzanne Clark of the UC Master Gardeners, Sonoma County.
The speakers advocated that we garden for butterflies by planting their host plants (where adult butterflies lay their eggs and where the offspring subsist) and by planting nectar plants (food source of adult butterflies). Other points: We must preserve their habitats; help establish food-embellished migratory corridors for monarchs heading to overwintering sites; avoid the use of pesticides; and support research.
The Pollinator Posse, geared toward protecting pollinators and creating habitat, also urged that we all get involved in conservation efforts, including rearing monarchs--bringing in the eggs and caterpillars from the outdoors to protect them from predators. Many "Monarch Moms" and "Monarch Dads" use zippered meshed containers, keeping the offspring safe from tachinid flies and wasps that lay their eggs in caterpillars and chrysalids.
Facilitator Mia Monroe, volunteer with the Xerces Society, coordinator of the Western Monarch Thanksgiving Count, and Muir Woods Park Ranger, pointed out the alarming monarch statistics:
In less than 20 years, the number of monarchs at overwintering sites in California has declined by 74 percent, a figure comparable to what's happening to the overwintering population in Mexico.
Among the other speakers:
- Amber Hasselbring, executive director of San Francisco's Nature in the City, who is establishing Green Hairstreak corridors in San Francisco neighborhoods.
- Andy Liu, landscape architect and garden designer specializing in butterfly habitat
- Sal Levinson, author, entomologist and noted speaker on butterfly habitats. She authored Butterfly Papercrafts Butterfly Papercrafts: 21 Indoor Projects for Outdoor Learning, a book geared for youngsters ages 5-12 and described as a key educational resource for teachers.
- Suzanne Clarke, UC Master Gardener from Sonoma County, who urged the participants to plant milkweed for monarchs: “Milkweed: If you plant it, they will come.” She sported a yellow t-shirt lettered with just that and a monarch image.
- Tim Wong, aquatic biologist at the California Academy of Science, and Barbara Deutsch who are involved in repopulating pipevine swallowtails in the San Francisco area
The summit drew some 250 to 300 people, who listened to the talks, visited the educational booths, learned about the metamorphosis from egg to caterpillar to chrysalis to adult, and what to plant to attract butterflies. Vendors offered books, posters, T-shirts, plants and butterfly habitats.
- Aesculus californica (California buckeye): Host plant of Echo Spring Azure butterfly
- Angelica tomentosa (woolly angelica) and A. archangelica: Anise Swallowtail
- Anisodontea sp. 'Strybing Beauty" (cape mallow): Vanessids, such as Vanessa atalanta, the Red Admiral
- Antirrhinums (snapdragons): Common Buckeye
- Asclepias (milkweed): Monarchs
- Asters: Field Cresentspot
- Ceanothus (all species): California Tortoiseshell, Echo Spring Azure, Gray Hairstreak
- Daucus carota (wild carrot, Queen Anne's lace): Anise Swallowtail
- Eriogonums (California buckwheat): Gray Hairstreak, Acmon Blue
- Foeniculum vulgare (fennel): Anise Swallowtail
- Grasses (California native Boutelouas, Festucas, Melicas, Muhlenbergias, Nassellas): Skippers
- Hollyhocks: Painted Lady, West Coast Lady, Common Checkered Skipper, Gray Hairstreak
- Keckiellas: Checkerspots, Common Buckeye
- Lathyrus (perennial natives, such as sweet pea): Silvery Blues
- Lavatera assurgentiflora (malvia): West Coast Lady
- Lippia repens (mat grass): Common Buckeye
- Lotus crassifolus variety otayensis (also known as Otay Mountain lotus): Acmon Blue
- Lupines (native perennial lupines like albifrons, arboreus, latifolius parishii, polyphyllus, propinquus, sericatus); Acmon Blue, some hairstreaks
- Mimulus aurantiacus (sticky monkey flower): Checkerspots, Common Buckeye
- Nasturtiums: Cabbage White
- Passiflora caerulea and some others (avoid bright red varies as they may be toxic): Gulf Fritillaries
- Penstemons: Checkerspots, Common Buckeye
- Sidalceas (checkered mallow): Painted Lady, West Coast Lady, Common Checkered Skipper, Gray Hairsteak
- Sphaeralceas (mallow): Gray Hairstreak, Painted Lady, West Coast Lady, Common Checkered Skipper
Good Bay Area nectar plants for butterflies, according to the Butterfly Summit, include California buckeye, brodiaecas (cluster lilies), milkweed, asters, butterfly bush (Buddlejas), cosmos, coreopsis, echiums, blanketflower (Gaillardia), dahlias, mint, rosemary, lavenders, marigolds, rosemary, phacelias, sunflowers, Mexican sunflower (Tithonia rotundifolia), Salvia clevelandii, Gilia capitata, Suromgas (lilac), verbenas, and zinnias.
Monarchs are especially fond of these nectar sources: butterfly bush (Buddleja), Mexican sunflower (Tithonia), asters, Echiums (Echium fastuosum or Pride of Madeira), and verbenas.
The National Wildlife Federation (NWF) says that "providing milkweeds and other nectar-rich flowers that bloom where and when monarchs need them is one of the most significant actions you can take to support monarch butterfly populations."--Monarch Nectar Plants, Inland California.
NWF also urges everyone to plant natives: "Although monarchs use a variety of nectar plant species, including exotic invasives such as ice plant and cape ivy, we recommend planting native species. Native plants are often more beneficial to ecoystems, are adapted to local soils and climates, and help promote biological diversity. They can also be easier to maintain in the landscape, once established."
Then think of watermelons and pumpkins.
All those crops will be discussed in a series of free webinars on Ensuring Crop Pollination in U.S. Specialty Crops, set Jan. 24 through March 28.
The webinars will feature five researchers with the Integrated Crop Pollination Project (ICP), including ICP co-principal investigator and pollination ecologist Neal Williams of the UC Davis Department of Entomology and Nematology. They are free and open to the public. Each will be 45 minutes to 60 minutes long.
Coordinating the series are Katharina Ullmann, national crop pollination specialist with the Xerces Society for Invertebrate Conservation, and Extension apiculturist and professor John Skinner of the University of Tennessee. Closely linked to UC Davis, Ullmann received her doctorate in entomology from UC Davis, studying with Williams.
"The majority of U.S. specialty crop growers depend on bees for pollination of their crops," Ullmann said. "Growers know that without adequate pollination, they would not be profitable. But what are the best pollination strategies for fruit, vegetable, and nut crops? What farm management practices can growers use to support bees and the crop pollination they provide?"
First to present will be Theresa Pitts-Singer, who collaborates with Williams. She will discuss Ensuring Almond Pollination on Jan. 24 and also deliver the ending seminar on March 28 on How to Manage Solitary Orchard Bees for Crop Pollination.
Williams will speak Feb. 28 on On-Farm Pollinator Benefits for Watermelon Pollination. An associate professor of pollination and biology and a Chancellor's Fellow, Williams serves as the faculty co-director of the UC Davis Honey and Pollination Center and is a member of UC Davis Agricultural Sustainability Institute. His applied research addresses the integration of wild and managed bees for pollination of diverse agricultural crops including seed production, row crops and orchards.
His research addresses a series of questions:
- Under what contexts, in terms of local management and landscape context, can native pollinators provide sufficient pollination for different crops?
- How can we enhance habitat and diversify agricultural systems to promote managed and wild bees?
- Do pollinators like honey bees and wild bees interact in ways to increase the overall effectiveness of crop pollination?
The answers to these questions will help alleviate the stress placed on honey bees, Williams says, and also "inform ways to more sustainability manage agricultural systems to promote biodiversity and production."
Williams has worked extensively in agro-ecosystems in California's Central Valley and in eastern Pennsylvania and New Jersey. His work in the East and West has helped form the basis for pollinator conservation planting guidelines. A continuing goal, he says, is to provide practical information that can be used to improve the long-term stability of pollination for agriculture in California, as well as promote pollinator conservation and management.
All speakers will discuss their research, and engage with the audience in discussing pollination of wild bees, honey bees and other managed bees in almond, blueberry, tree fruit, pumpkin, and watermelon. Each registered attendee will later receive a link to the slides.
To register, attendees can click on each link (note that all times here are 11 a.m., Pacific Time (consult your time zone):
- Jan. 24: Ensuring Almond Pollination (Theresa Pitts-Singer, USDA-ARS and Utah State University)
- Jan. 31: Pollinating Highbush Blueberries: Bees Bring Bigger Berries (Rufus Isaacs, Michigan State University)
- Feb. 14: Pollinating Apples and Cherries East of the Rockies (Julianna Wilson, Michigan State University)
- Feb. 28: On-Farm Pollinator Benefits for Watermelon Pollination (Neal Williams, University of California, Davis)
- March 21: Ensuring Pumpkin Pollination (Shelby Fleischer, Pennsylvania State University)
- March 28: How to Manage Solitary Orchard Bees for Crop Pollination (Theresa Pitts-Singer, USDA-ARS and Utah State University)
The webinar series will be hosted by eXtension.org, an online Cooperative Extension network. Funding will be provided by the Integrated Crop Pollination Project, a USDA-NIFA Specialty Crop Research Initiative Grant (#2012-51181-20105). Plans are to offer continuing education credits for certified crop advisors.
That's the sound of success.
It finally happened. The beleaguered rusty-patched bumble bee, Bombus affinis, is now listed by the U.S. Fish and Wildlife Service as an endangered species, the first bee in the continental United States to be listed under the Endangered Species Act.
So many folks helped spearhead this project. Bumble bee expert Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis, and co-author of Bumble Bees of North America: An Identification Guide (Princeton University) helped sound the alarm.
Thorp co-authored a 2010 petition seeking an endangered status for Bombus affinis. The Xerces Society of Invertebrate Conservation, along with Thorp and others, submitted the petition to the U. S. Fish and Wildlife Service in 2013. In 2015, agency officials agreed to consider it. In 2016, they proposed protection. Then on Jan. 10, 2017, the Fish and Wildlife Service listed the rusty-patched bumble bee as an endangered species. (See Xerces press release.)
Other key players in making this all happen included natural history photographer/filmmaker Clay Bolt and his friends at the Day's Edge Productions, which created the award-winning film, A Ghost in the Making: Searching for the Rusty Patched Bumble Bee with support from the Xerces Society and others. The result: nearly 200,000 persons signed a petition seeking endangered status for the bee.
The rusty-patched bumble bee was once found in 28 states in the eastern and upper midwest United States, along with the District of Columbia and two Canadian provinces. Since the late 1990s, however, its population has declined by nearly 90 percent, according to Sarina Jepsen, director of endangered species for the Xerces Society.
"The rusty patched bumble bee is threatened with extinction," Jepsen wrote in the petition. "Possible causes of its decline include pathogens, habitat loss or degradation, pesticide use, and climate change. Reduced genetic diversity, which could be a result of declining, isolated populations caused by any of the aforementioned factors, likely also threatens this species with extinction. Furthermore, existing regulations are wholly inadequate to protect this species."
Jepsen described bumble bees as "iconic pollinators that contribute to our food security and the healthy functioning of our ecosystems."
Enter Clay Bolt who set out to find, photograph and document the critically imperiled bumble bee. He moved from state to state, habitat to habitat, museum to museum, meeting with scientists and conservationists. Finally, he found the living breathing rusty-patched bumble bee in the University of Wisconsin arboretum. You can see his excitement and learn about his incredible journey in the amazing Ghost in the Making.
Bolt related that he first became aware of the plight of the rusty-patched bumble bee while looking at specimens in the collection at Great Smoky Mountains National Park. "There was a stuffed passenger pigeon in the same room, frozen in time, but no longer among us in nature," he told us. "It was once the most numerous bird on the planet and then it was no more. This has always haunted me. I decided then that I had to do everything in my power to attempt to bring more attention to this beautiful little bee before it went the same way."
With friends from Day's Edge Productions and the Xerces Society, Bolt made the film about the bee, helped develop the petition, and spoke on Capitol Hill and other high-profile events to spotlight its plight. "Through all of this, I kept thinking back to seeing this amazing little animal in the field," Bolt said. "Watching it fly. Witnessing it do what it had been doing for thousands of years. It had no idea that its fate was in our hands."
"I am just so encouraged and grateful for the public's outcry in support of this species," Bolt said. "This was an effort that would have never been possible without so many people working together to see it through. I am grateful that my images played even a small part in this historic occasion. These are the moments that make all of the hours of work and worry worthwhile."
One observation in Ghost in the Making particularly resonates: "We spend so much time and effort making life better for ourselves, the least we can do is make life possible for this bee." The film advocates that we all do our part: provide flowers, a safe place to nest, and a pesticide-free environment.
How many other bumble bees should be listed as endangered? "That's difficult to answer, mainly due to a lack of good information," said Thorp. "Most of our bumble bee species seem to be doing well according to our most recent assessments. But at least one eastern cuckoo bumble bee may be declining because its host bumble bees have declined. About a quarter of our bumble bees may be at risk, but we need more information. One that used to be common here in the Central Valley, Bombus sonorus, basically disappeared from our area about a dozen years ago, but it is doing well in the southern part of its range in southern California and Arizona."
Meanwhile the U.S. Fish and Wildlife Service is reviewing three other species of bees for possible inclusion as endangered. They include Franklin's bumble bee, the western bumble bee and the yellow-banded bumble bee.
Thorp, who has been monitoring Franklin's bumble bee, Bombus franklini, since 1998 (See Dec. 12 Bug Squad), hasn't seen the bumble bee in 10 years within its five-county range of southern Oregon and northern California. He doesn't want to say the "E" word--extinct. Not yet. He thinks this may be the year he'll find it.
This week, however, is a cause for celebration. The rusty-patched bumble bee is now an endangered species, in danger of extinction, and we can now begin the process to protect it and recover it.
We walked into our little pollinator garden in Vacaville, Calif., this afternoon to cut a few tropical milkweed stems to feed the indoor caterpillars, and there, hidden beneath a leaf, was a tiny caterpillar.
Well, hello, there! Aren't you a little late? The monarchs have been overwintering along coastal California for a couple of months. Your parents did not get the memo.
This uncharacteristic weather we're having--autumn temperatures soaring into the 70s here in recent weeks--means the milkweed is still growing and the caterpillars are, too.
We've pruned all of the tropical milkweed down to the ground except for one plant that's still flowering. We're keeping it. Food is scarce for the honey bees, syrphid flies and other pollinators.
Meanwhile, Tiny Caterpillar is a new addition to our indoor habitat. Ours is just a small-scale conservation project of rearing and releasing monarchs to help boost the declining monarch population. So far this season, our total is 54. That's 54 that may have been eaten by birds or consumed inside-and-out by parasitoids such as the tachinid flies, which lay their eggs inside the caterpillars or chrysalids. Overall, about 2 or 3 percent of the monarchs make it all the way through their life cycle, from egg to caterpillar to chrysalis to adult, scientists estimate.
Here are the basics of how we rear them, but all Monarch Moms and Monarch Dads do it differently.
- Grow milkweed species, the host plant of the monarchs. We have four different species in our pollinator garden:
--Asclepias fascicularis, narrowleafed milkweed
--Asclepias speciosa, broadleaf milkweed
--Asclepias tuberosa, a Midwest favorite
--Asclepias curassavica, tropical milkweed
- In addition to milkweed, plant other nectar-producing plants for your monarchs and other pollinators. The monarch favorites, at least in our yard, include Mexican sunflower (Tithonia), an annual that grows here from April through November (in fact it's still blooming), butterfly bush (Buddleia), and Lantana.
- When you see caterpillars on the milkweed, you'll need to protect them from predators, such as birds, tachinid flies and wasps by bringing them indoors. Add water to a heavy, narrow-necked, flat-bottomed bottle (we use Patron tequila bottles, compliments of our friends). Tuck the milkweed stems, with the 'cats still on the stems, in the tequila bottle. Then place the bottle in a meshed, zippered butterfly habitat, such as the ones from the Bohart Museum of Entomology. You can also buy meshed, zippered laundry bags from stores.
- Be sure to keep the milkweed fresh. Mist it lightly, and add new milkweed daily. Clean the frass from the bottom of the habitat.
- Watch caterpillars eat their fill and then pupate. You'll see the jade-green chrysalids, rimmed in gold, hanging from the top of the habitat.
- When the monarchs eclose, wait for their wings to dry before releasing them. We usually release them after four or five hours--if it's not cold or rainy. Food? They usually won't eat for 24 hours. If the weather is inclement and we can't release them right away, we feed them. We dip a cotton ball into a mixture of honey and water, and place it on a tray, along with a fresh flower or a slice of fruit, such as cantaloupe or watermelon. Some folks feed them a sugar and water mixture. Some use sports drinks such as Gatorade. Mona Miller, administrator of the Facebook page, Raising Butterflies and Moths for Conservation, tells how to feed monarchs on her YouTube channel. She uses 2 tablespoons of water (heated) and 1/2 teaspoon of raw organic honey (more amino acids and protein). She cools the mixture and places in a colorful cap lid (yellow, red, orange).
- When it's time to release a monarch, we just unzip the container. Sometimes we gently cradle the monarch, and then open our hands and watch it go. Some monarchs take off immediately. Others linger on our hands or head for a nearby plant.
- After you release each batch of monarchs, clean the container with soapy water and a little bleach.
Some excellent resources to get you started and keep you going:
- Xerces Society: Monarchs for Conservation and Project Milkweed
- The Beautiful Monarch, Facebook page administered by Holli Webb Hearn
- Raising Butterflies and Moths for Conservation, Facebook page administered by Mona Miller