It's good to see butterflies, especially monarchs, getting so much press.
Now let's see if we can press the issue.
The Washington Post just published an article in its style section: "Butterflies Were Symbols of Rebirth. Then They Started Disappearing," chronicling the history--as we know it--of butterflies. For his in-depth piece, reporter Dan Zak interviewed butterfly guru Art Shapiro, distinguished professor of evolution and ecology at UC Davis, who has monitored the butterfly population in Central California since 1972 and maintains a research website.
The Washington Post reporter mentioned the monarch butterfly summit held Feb. 28 in the Putah Creek Lodge, UC Davis, where invited guests of the Environmental Defense Fund discussed "Recovering the Western Monarch Butterfly Population: Identifying Opportunities for Scaling Monarch Habitat in California's Central Valley."
How serious is it? "The latest population surveys indicate that monarchs overwintering on the central coast have declined 86% since last winter and now total 0.5% of their historical average," according to the agenda.
Shapiro, one of the speakers, delivered a presentation on "What We Don't Know and What We Know That Ain't So About Monarchs" in which he declared that "monarchs are on life support in California, and we are reduced to prescribing placebos." (See Bug Squad blog.) "I never saw a single wild Monarch larva in 2018—the first time since I became butterfly-aware in 4th or 5th grade!" he said.
In his Washington Post piece, published March 6, Zak wrote: "There's compelling evidence that pesticides, deforestation and habitat loss are to blame for monarch decline. Climate change sharpens every threat by altering weather patterns, extending droughts, strengthening storms. It's easy to conclude, then, that we are responsible....Shapiro says we don't fully understand what's happening to butterflies, but he can't shake a feeling of responsibility."
“I feel like a doctor who has a patient he's known his entire life, and the patient is obviously dying, and the doctor and his colleagues have been unable to determine why — so they can't recommend treatments,” Shapiro told the reporter. “It's a level of frustration where I'm watching things that I love go away, and there's nothing I can do about it but just stand there.”
We experienced that a little of that level of frustration last year in our pollinator garden in Vacaville. We saw--and reared--only 10 caterpillars in 2018. Compare that to 2016 when we reared and released more than 60 monarchs.
In 2016, we'd commonly see seven or eight at any given time all day long in the late summer and early fall. They'd stop for some flight fuel before winging it over to the California coast to overwinter. On Labor Day, 2016, we photographed a tagged migratory monarch from Ashland, Ore. nectaring in our garden. It was part of a citizen science project conducted by Washington State University entomologist David James.
Very few migratory monarchs fluttered into our garden in 2018. Where are all the monarchs? Something indeed was--and is--happening.
"For thousands of years, humans have looked to butterflies as a reassuring symbol in times of change," Zak wrote. "The Earth now is changing, and butterflies have become a symbol of something else: loss."
As Shapiro said in his presentation in the Putah Creek Lodge:
- Consider a doctor faced with a patient in rapid decline. All tests have failed to identify the cause. What is the doctor to do? You can't prescribe treatment for an undiagnosed illness, can you? You can make a wild stab at a prescription on the basis that the patient is going to die anyway, and MAYBE, just maybe, this drug will do some good. Or you can prescribe a placebo, just to reassure the patient that you are doing something. That's where things get interesting. Occasionally a patient improves drastically on a placebo. Maybe he would have improved anyway; there's no way of knowing. Suppose our patient has a complete remission despite having received only a placebo. Does our doctor convince himself the placebo cured him?
As of right now, the Monarch is on life support in California, and we are reduced to prescribing placebos. If our patient comes back from the brink—as history suggests it may well—will we convince ourselves that our placebos worked? Probably. And that's not how to do science. That's what philosophers call the fallacy of post hoc, ergo propter hoc.
We can do can do better than that!
Meanwhile, Shapiro will be teaching a UC Davis graduate student course, "The Science of the Monarch Butterfly," on Tuesday nights, starting April 2, during the spring quarter. The course is set for 8:10 to 10 p.m. every Tuesday in Room 2342 in Storer Hall, located off Kleiber Hall Drive. He's inviting citizen scientists or others interested in the science of the monarchs to audit the course, for free. No reservations are required.
The article: "Neonicotinoid Ppesticide Exposure Impairs Crop Pollination Services Provided by Bumblebees."
Seeking his expertise, journalists are contacting Thorp, distinguished emeritus professor of entomology at the University of California, Davis, who maintains an office at the Harry H. Laidlaw Jr. Honey Bee Research Facility, and also works at the Bohart Museum of Entomology.
The research, by a team of six UK colleagues, indicates that neonics are hindering the pollination services of bumble bees. Corresponding author is Nigel E. Raine of the School of Biological Science, Royal Holloway University of London and his team wrote in the abstract:
"Recent concern over global pollinator declines has led to considerable research on the effects of pesticides on bees. Although pesticides are typically not encountered at lethal levels in the field, there is growing evidence indicating that exposure to field-realistic levels can have sublethal effects on bees, affecting their foraging behaviour, homing ability and reproductive success Bees are essential for the pollination of a wide variety of crops and the majority of wild flowering plants but until now research on pesticide effects has been limited to direct effects on bees themselves and not on the pollination services they provide. Here we show the first evidence to our knowledge that pesticide exposure can reduce the pollination services bumblebees deliver to apples, a crop of global economic importance. Bumblebee colonies exposed to a neonicotinoid pesticide provided lower visitation rates to apple trees and collected pollen less often. Most importantly, these pesticide-exposed colonies produced apples containing fewer seeds, demonstrating a reduced delivery of pollination services. Our results also indicate that reduced pollination service delivery is not due to pesticide-induced changes in individual bee behaviour, but most likely due to effects at the colony level. These findings show that pesticide exposure can impair the ability of bees to provide pollination services, with important implications for both the sustained delivery of stable crop yields and the functioning of natural ecosystems."
The researchers studied Thiamethoxam, one of the neonics.
Thorp, who was not involved in the research, is a global expert on bumble bees, as well as other bees. He co-authored Bumble Bees of North America: an Identification Guide (Princeton University) published in 2014, and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday), also published in 2014.
Thorp was quoted today in the well-researched Washington Post piece, "New Research Reignites Concerns that Pesticides Are Harming Bees," written by freelance journalist Chelsea Harvey, who specializes in environmental health and policy.
“Most of the studies in the past have focused on direct effects on the bees, both the adults and the larvae,” Thorp told Harvey. "These can include effects on bee mortality or reproduction...“This study now clearly demonstrates that in addition to effects on the bees, both direct effects and sublethal indirect effects, that these effects are influencing their ability to pollinate plants. And they used apple as an example of this, as an important crop.”
The topic is quite controversial, but the importance of pollination is not. Inadequate pollination can lead to unfavorable effects on agricultural crop production. For example, bumble bees may not forage on the apple blossoms as much or as long. That could lead to poor fruit quality and decreased apple production.
Why are bumble bees important? “They're extremely important in pollination of our native ecosystems, and many of them…are important contributors to crop pollination," Thorp told the Washington Post.
Bumble bees are known for their specialized pollination of tomatoes and watermelon, but they also pollinate many other agricultural crops.
Thorp points out that with the decline of the honey bee population, the work of other pollinators is becoming increasingly crucial.
Thorp anticipates that the study will open doors for more research involving neonics and wild bees. "Even if the study can't be generalized to all bees or all crops, it raises more questions in the ongoing debate over pesticide use in the U.S.," Harvey pointed out in her news article.
“I think it's kind of a wake-up call to growers that they ought to be paying more attention to what they're putting on their crops,” Thorp told Harvey. “Because it's coming right out of their pocket as well if they're damaging the ability of pollinators that they rely on to pollinate their crops.”
Thorp has long been part of the mission to save the declining bumble bee population. He works closely on bumble bee conservation with Xerces Society for Invertebrate Conservation, headquartered in Portland, Ore.
The Xerces Society emphasizes the importance of bumble bees on it website. ""Bumble bees are important pollinators of wild flowering plants and crops. They are generalist foragers, and thus do not depend on any one flower type. However, some plants rely on bumble bees to achieve pollination. Loss of bumble bees can have far ranging ecological impacts due to their role as pollinators. In Britain and the Netherlands, where multiple pollinator species have gone extinct, there is evidence of a decline in the abundance of insect pollinated plants."
"Bumble bees are able to fly in cooler temperatures and lower light levels than many other bees, which makes them excellent crop pollinators," according to Xerces. "They also perform a behavior called 'buzz pollination,' in which the bee grabs the pollen producing structure of the flower in her jaws and vibrates her wing muscles. This causes vibrations that dislodge pollen from the flower. Some plants, including tomatoes, peppers, and cranberries, benefit from buzz pollination."
You won't find anyone more passionate about building a better bee than bee breeder-geneticist Susan Cobey, who holds dual appointments at the University of California, Davis and Washington State University.
For one thing, her spring workshops on queen bee rearing and instrumental insemination at the Harry H. Laidlaw Jr. Honey Bee Research Facility at UC Davis are already filled and there's a waiting list. Those on the waiting list--or at least some of them--are expected to register for her Washington state summer classes.
Those should fill up fast, too.
Cobey and her work are mentioned today in a Washington Post article, "In search of a better bee."
A key enemy of honey bees is the varroa mite, a parasitic critter that feeds on bee brood. Sometimes you'll even see it clinging to a foraging adult.
Cobey seeks to improve her stock. This includes building a better hygienic bee that can remove the varroa mites from the cells and the brood.
It's not an easy task.
"As vital as the hygienic bee is, the breeder must preserve desirable traits--a reluctance to sting or swarm, for example, as well as genetic diversity in a hedge against future diseases or pests," wrote Washington Post reporter Adrian Higgins.
"That's why gains are so slow," Cobey told her in the news story. "I would say we are just in the infancy of bee breeding."
Higgins wrote that Cobey is one of only a handful in the country skilled at artificially inseminating "virgin queens from known drone stock."
Why artificial insemination? When a virgin queen bee mates with drones in the drone congregation area (she mates in flight with a 12 to 20 drones or more), the breeding stock can't be controlled.
With queen bee insemination, it can be.
That's one of the reasons why Cobey's workshops draw students from throughout the world, and why they fill up fast.