Butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, spotted a female monarch butterfly at 1:35 today.
As he mentioned in his email: "So, at 1:25 p.m. a female monarch flew directly over my head, roughly 8' off the ground, near the corner of Oak Avenue and 8th Street. It was headed northeast very lazily."
Shapiro noted that Kathy Keatley Garvey saw a monarch in Benicia on Jan. 23, "so this is the second sighting known to me this year in this general area. If there are really only 3000 or fewer overwintered in the whole state, I guess we won the lottery!"
So, the count as we know it:
- Monarch butterfly, gender unknown, flying over 115 West G St, Benicia, on Feb. 23, Garvey sighting
- Monarch butterfly, a male, that the Garveys reared in west Vacaville and released on Feb. 25
- Monarch butterfly, a female, flying near the corner of Oak Avenue and 8th Street, Davis, on March 2, Shapiro sighting
Now some folks are blaming tropical milkweed, Asclepias curassavica, a non-native, as a serious threat in the massive decline of the monarch population.
Don't blame tropical milkweed, agree Shapiro and monarch researcher David James, an entomologist and associate professor at Washington State University (WSU).
James told us in an email: "I have been involved with monarchs for 43 years, and the single, overriding thing that I have learned is that the monarch is a highly adaptable creature! It has an incredible ability to adjust to changing environmental circumstances. In Australia, it took less than 100 years to change its core physiology as part of adaptation to a different climate. Adapting to man-made environmental challenges may take monarchs a while but I believe it can happen."
"I believe that the widespread and intensive use of neonicotinoid insecticides is one likely factor behind the current monarch population decline," James says. "But even with insecticides, insects can develop resistance over generations. The few monarchs that are alive and well in California currently are the survivors, those that have beaten the perils stacked against them. Clearly, we need to try and make life as fruitful as possible for these survivors, to aid in their population recovery. These monarchs will produce progeny that are also ‘fitter' than the general population and we need to ensure that milkweed is there for them, particularly during spring in California."
"The monarch as a species is particularly good at trying different things," James points out. "Thus, while the majority of the population does one thing (like migrate and overwinter), there is always a significant subset exposed to the same environment, that decides to do something different, like not migrate. Most of these of course will die but in some circumstances, some locations, the outcome may be good, giving another option for continuation of the species, should it become necessary. We may be seeing this now with the rise in winter breeding of monarchs in warmer parts of interior California like the LA Basin and SF Bay Area. There is also evidence for the first time of breeding winter monarch survival in far southwestern Oregon."
A post on texasbutterflyranch.com touched on the native/non-native milkweed controversy. "David James takes issue with the loud and persistent claim that non-native milkweeds pose serious threats to monarch butterflies and the viability of their migrations. When asked if he thinks the technically non-native tropical milkweed poses a dire threat to monarch butterflies, James' answer was emphatic."
No, he does not. "Not at all, in fact," he told them.
You can follow David James' research and observations on his group's Facebook page, Monarchs of the Pacific Northwest at https://www.facebook.com/MonarchButterfliesInThePacificNorthwest.
On Jan. 12 James posted a graph showing "the number of observations of monarch larvae/pupae (as recorded on I-Naturalist) in the San Francisco Bay area during November/December for every year since 2015. The graph showed a huge (>5X) increase in observations in 2020 compared to each of the the previous 6 years. I have now extracted data on monarch reports for January 2021 and compared them to the previous six years (see graph below). Once again, the data show a large increase in reports of both adult and immature stage monarchs during the past month in the SF Bay area. In fact, the increase is greater than for Nov-Dec. The average number of larvae/pupae reported on I-Nat during January from 2015-2019 was 1.0. This year the number was 63. Similarly an average of 5.0 adults were reported for January during 2015-19, yet this year there were 58 sightings reported to I-Nat. Of course some of this increase can be explained by increased use of I-Nat in these covid times to report sightings, but I doubt that this explains it all. Interestingly, there were signs last January of an increase in sightings when 10 larvae and 12 adults were reported. But the numbers in January 2021 are on another level."
James' work draws such comments as "You rock, Dr. David James! Thank you for speaking common sense and not regurgitating a hard line which equates to death for the monarchs when milkweed is purposely cut and no milkweed is available for the next generation to consume! I look forward to more findings from you and your honest research reporting. Thank you so much for all you do to help the monarchs thrive not just survive!"
Meanwhile, anyone else see any monarchs flying around the Bay Area and/or in Yolo and Solano counties?
So, folks, if you're in their migratory pathway and anticipate seeing them head toward their overwintering sites in coastal California, don't get your hopes up.
They're not coming. They are either non-existent or few and far between.
But we remember when they did.
Back on Labor Day, Sept. 5, 2016, a male monarch tagged "email@example.com A6093" fluttered into our pollinator garden in Vacaville. Washington State University entomologist David James traced it to citizen scientist Steve Johnson of Ashland, Ore., who had tagged and released it on Sunday, Aug. 28.
James calculated "No. A6093" flew 285 miles in seven days or about 40.7 miles per day to reach our Vacaville garden, which apparently is in a monarch migratory pathway. "Clearly this male is on his way to an overwintering colony and it's possible we may sight him again during the winter in Santa Cruz or Pacific Grove!” he said at the time. (No sightings reported.)
Still, it was a very good year for monarchs in 2016, as compared to previous years. We reared more than 60 in 2016. We saw dozens of migrating monarchs fueling up on nectar from the Mexican sunflowers (Tithonia rotundifola) and butterfly bush (Buddleia davidii). They arrived tattered and torn, and some could barely fly.
But come they did.
Not this year.
"It's been a very poor year for monarchs in the Pacific Northwest," James said. "In Washington, we had just two confirmed sightings of monarchs! This is the worst showing since I started taking records in 1999. I thought 2019 was bad (eight monarchs) but 2020 beat it."
"There were a handful of sightings in central and northern Oregon but they largely failed to cross into Washington," the entomologist said. "This is simply a result I believe of a very small overwintering population that had difficulty populating California and southern Oregon let alone locations further north."
"If future overwintering populations do not exceed more than 30,000, then this is what we can expect for the future; the monarch to be a rarity in Washington and BC."
Johnson, who rears monarchs in a vineyard in Ashland, says it was "a very poor year in the vineyard. We have three chrysalids right now and that will probably be it for us in the vineyard this year. They come from three 'cats that we found on the same day. We have seen far fewer monarchs than in any of the past years. Overall, to my knowledge, it has been a grim year in Oregon except for some isolated pockets."
Southern Oregon seemed to fare a little better for monarchs in the Pacific Northwest this year, James said, but "as Steve said, it was still way less than recent years."
"Idaho had quite a few monarchs, maybe as many as southern Oregon, but these arrived and bred from--I believe-- migrants that came from Mexico," the WSU entomologist said. "Populations in Arizona and Utah were also reasonable this summer. 'Leakage' 'of northerly spring migrants from Mexico is the ‘saving grace' of monarch populations in the West and may be the reason why monarchs can persist long-term in the West. This was a theory expounded by the late Lincoln Brower and I believe it has a lot of merit."
Johnson noted that the air quality in Ashland "at the moment (this morning) is 415—very hazardous."
How does all that poor air quality, all that smoke and ash from the wildfires raging across the West affect the migrating monarchs?
Thanks to James' tagging program and cooperators like Johnson, James now has "some limited data indicating monarchs do NOT have a problem migrating in very poor quality air. These data will appear in a publication I am preparing. Tagged monarchs released into poor quality air flew just as far and lived just as long as those that were released into good air."
Butterfly guru Art Shapiro, distinguished professor of evolution and ecology at UC Davis, who has monitored butterfly populations in Central California since 1972, has seen only six monarchs all year (the first one in Sacramento on Jan. 29) and "no eggs and no caterpillars at all." (See Bug Squad blog on his comments on "California monarchs on life support")
Naturalist Greg Kareofelas of the Bohart Museum of Entomology, UC Davis, has seen only one monarch all year and it was a female laying an egg on his milkweed in Davis. He is in the process of rearing it from egg to caterpillar to chrysalis to adult. It's a chrysalis now.
Lynn Kimsey, director of the Bohart Museum and UC Davis professor of entomology, and UC Davis forensic entomologist Robert Kimsey have not seen any in their Davis garden.
This year our Garvey family has managed to collect dozens of eggs and 'cats from our garden and rear them in three different batches. First batch: 5. Second batch: 11. The third batch? As of Sept. 1, we've reared and released 37 monarchs, with one chrysalis remaining. No. 38 should eclose in a few days.
Incredibly, our Vacaville pollinator garden seems to some kind of monarch magnet.
"I think Kathy and one gardener in the East Bay who is having a similar experience have all the monarchs in the region in their yards," Shapiro commented. "Very bizarre."
Very bizarre, indeed.
You're not thinking of root-knot nematodes, major pests of potatoes.
But potato growers and nematologists are.
So are the editors of the scientific journal, Nature Plants. Their current edition showcases research on root-knot nematodes by Washington State University (WSU) scientists Lei Zhang and Cynthia Gleason, and a commentary by UC Davis nematologist Shahid Siddique and colleague Clarissa Hiltl of the University of Bonn, Germany.
“Plant-parasitic nematodes are among the world's most destructive plant pathogens, causing estimated annual losses of $8 billion to U.S. growers and of nearly $78 billion worldwide," according to Siddique, an assistant professor in the UC Davis Department of Entomology and Nematology.
“Most current control methods rely on chemical nematicides, but their use is increasingly limited due to environmental concerns," Siddique and Hiltl wrote in their News and Views column, New Allies to Fight Worms.
They commented that the WSU scientists' proposed alternative pest management strategy--naturally occurring molecules or plant elicitor peptides (Peps)—shows promise: “Engineering a naturally occurring rhizobacterium to deliver Peps to the plant root system offers a new opportunity in integrated pest management.”
It's better to build up the host plant's immune system rather than directly target the pathogen with chemical nematicides which “are highly toxic and have negative effects on the ecosystem," Siddique told us.
The root-knot nematode Meloidogyne chitwoodi is a noted pest of potato production in the Pacific Northwest. Idaho leads the nation in commercial potato production, followed by Washington. Oregon ranks fourth. California, which ranks eighth, grows potatoes year around due to its unique geography and climate.
The WSU scientists demonstrated the effective use of Peps to combat root-knot nematodes in potato (Solanum tuberosum). They engineered a bacteria, Bacillus subtillis, to secrete the plant-defense elicitor peptide StPep1. They wrote that pre-treatment of potato roots “substantially reduced root galling, indicating that a bacterial secretion of a plant elicitor is an effective strategy for plant protection." (See article.)
“Besides chemical nematicides, methods of nematode management include the use of crop rotation, microbial biocontrol agents, cover crops, trap crops, soil solarization, fumigation and resistant plant varieties,” wrote Siddique and Hiltl. “However, several of these strategies are not effective or available for all crops. Nematicides are highly toxic, and their use is strictly limited due to environmental concerns. Resistant plants are often ineffective or unavailable. Microbial biocontrol agents have produced inconsistent results. In this context, the current work provides a new opportunity to manage plant-parasitic nematodes by combining two progressive strategies: the use of plant elicitors to enhance crop resistance to pathogens and the use of B. subtilis to deliver.”
According to the UC Statewide Integrated Pest Management Program (UC IPM), root-knot nematodes "usually cause distinctive swellings, called galls, on the roots of affected plants. Infestations of these nematodes are fairly easy to recognize; dig up a few plants with symptoms, wash or gently tap the soil from the roots, and examine the roots for galls. The nematodes feed and develop within the galls, which can grow as large as 1 inch in diameter on some plants but usually are much smaller."
"Nematodes are too small to see without a microscope," UC IPM points out. "Often you become aware of a nematode problem by finding galled roots on a previous crop. However, you also can use a simple bioassay to detect root knot nematodes in garden soil. Melons seeded in pots in moist soil collected from the garden will develop visible galls on the roots in about 3 weeks when pots are kept at about 80ºF if root knot nematodes are present. As a comparison, melons planted in heat-sterilized soil won't develop galls."
First there were the Africanized honey bees, which sensationalists called "the killer bees."
Don't even mention "assassin flies" or "bullet ants" or "deathwatch beetles."
Now there are the Asian giant hornets (AGH), Vespa mandarinia, which sensationalists have dubbed "murder hornets."
"It's ridiculous to call them murder hornets,” says noted UC Davis wasp expert and researcher Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology, UC Davis Department of Entomology and Nematology.
“It's no more likely to sting and kill a human than a honey bee,” said Kimsey, a two-term past president of the International Society of Hymenopterists, an organization that studies bees, wasps, ants, and sawflies.
“Actually it's less likely, as honey bee venom packs quite a punch and it is exclusively designed to defend against vertebrates,” she said.
“The colony everyone is hyperventilating over was actually found on Vancouver Island, British Columbia, last September when it was destroyed and then a single, dead hornet was found in December in Blaine, Wash.,” Kimsey said. “There is no evidence that there are any more hornets in the vicinity of Vancouver or anywhere else on the West Coast.”
These were the first detections of this species in North America, but there may be more, according to the Washington State Department of Agriculture (WSDA). Beekeepers have reported “observations” (which may or may not be the same species) dating back to October 2019, according to officials in Washington State University's Department of Entomology and Cooperative Extension. They and the beekeeping organizations want to know what's out there and they want folks to keep a lookout for them.
Said Kimsey: “A decade or more ago there was a colony of another species, Vespa asiatica, reported near the Port of Long Beach but nothing ever came of that either. A European species, Vespa crabro, was introduced into the East Coast perhaps a century ago and it is now fully established in the southeastern U.S.”
Kimsey points out that insects often come in cargo boxes from Asia to U.S. ports, establish colonies, and expand their range.
A soon-to-be-published article in the Entomological Society of America's journal, Insect Systematics and Diversity, promises to shed more light on the genus and the history of introductions in the United States.Kimsey and colleagues Allanmith-Pardo of the USDA and James Carpenter of the America Museum of History, New York, co-authored the review article.
In the abstract, the authors define Vespa as social wasps that are “primarily predators of other insects, and some species are know to attack and feed on honey bees, Apis mellifera, which makes them a serious threat to apiculture.”
“Vespa nests can be physically large, with over 1,000 workers, but usually with hundreds of workers,” they wrote. “Nests can be aerial, attached to tree branches or in shrubs, in crevices, under eaves or underground depending on the species. Depending on the latitude, nests can be either annual, started by a new queen every spring, or perennial, where young queens take over from old ones. Colonies in warm tropical climates tend to be perennial.”
Washington State University (WSU) Extension recently published an AGH fact sheet, the work of three scientists: Susan Cobey, bee breeder-geneticist and husband Timothy Lawrence, county director of Island County Extension (both formerly of UC Davis), and Mike Jensen, county director of Pend Oreille. (See https://bit.ly/2SA3TxS)
Yes, hornets are huge. They measure about two inches long, and the queens can fly up to 20 miles per day, said Cobey, who examined specimens in Japan last December and shipped some of them to WSU.
The WSU scientists wrote that AGH “is the world's largest species of hornet, native to temperate and tropical Eastern Asia low mountains and forests. The hornet is well adapted to conditions in the Pacific Northwest.”
“The primary purpose of venom is defense against predators by inflicting pain and damage,” they wrote. ”Vespa mandarinia is one of the two most venomous known insects in the world.. The amount of venom each wasp delivers (4.1 μl/ wasp) has designated V. mandarinia as the most venomous insect. In comparison, the honey bee has about 0.6μl/bee. When foraging for food in spring, the AGH is not highly defensive – unless its nest is disturbed. Late summer and fall, with the high demand for protein, they become very aggressive when attacking or occupying a honey bee colony.”
“It is critical that we identify, trap, and attempt to eliminate this new pest before it becomes established and widespread,” they wrote. “Attempts to contain the spread and eradication of this invasive insect will be most effective in trapping queens during early spring before their nests become established. Finding the nests can be a bit of a challenge. Their nests are typically in the ground though they can also be found under overhangs and within wall voids. The AGH is a strong flier and often will fly up and away and have an extensive flight range. Thus tracking can be difficult.”
They advise residents to “proceed with extreme caution and contact WSDA immediately. Do not try to exterminate the nest yourself.”
Entomologists call them Asian giant hornets or Vespa mandarinia.
Could we just go back to calling them Asian giant hornets or AGH or Vespa mandarina?
Meanwhile, scientists want to know where the monarchs are in the early spring. When the iconic butterflies head inland from their coastal overwintering sites, where do they go?
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.
UC Davis alumnus Christopher Jason, a technician in the Schultz lab, said WSU researchers are collaborating with the Elizabeth Crone lab at Tufts University; Xerces Society of Invertebrate Conservation; and UC Santa Cruz. Crone, a biology professor recently on a research sabbatical at UC Davis, told the UC Davis Department of Entomology and Nematology at a seminar Jan. 30 (the same day that Shapiro sighted a monarch in Sacramento) that more research needs to be done on where monarchs are in the spring, as that is a "critical point in their life cycle." Monarch populations are at their lowest at this time of year, Crone said, and individual butterflies may be at their "weakest right after their long overwintering diapause.”In an email, Jason reiterated that "The Western Monarch Mystery Challenge is a campaign to find out where western monarch butterflies are in early spring. We know they spend the winter months (November to February) in groves along the California coast, and start breeding in central California in May, and in some cases, as early as February. However, we know a lot less about where they are and what they're up to in February, March, and April. Solving the mystery of where western monarchs spend the spring is central to conserving and restoring the phenomenon of monarch migration in the West."