A virtual seminar to be hosted by the UC Davis Department of Entomology and Nematology on Wednesday, Oct. 21 should draw widespread interest, especially with the discovery last month of Aedes aegypti in Yolo County.

Mosquito researcher Maria Onyango, a postdoctoral associate at the New York State Department of Health,  Albany, N.Y.,  will speak on "The Impact of Zika Virus Infection on the Metabolites and Microbiome of Aedes albopictus" from 4:10 to 5 p.m. The Zoom seminar is open to all interested persons; click here for the form to register and obtain the Zoom link. 

Aedes albopictus, known as the Asian tiger mosquito, is a close relative of Aedes aegypti, the yellow fever mosquito. Both invasive species are moving through California. (See California report of the two species, and the Center for Disease Control and Prevention's estimate potential range of the two species in the United States.)

Medical entomologist-geneticist Geoffrey Attardo of the UC Davis Department of Entomology and Nematology, who collaborates with Onyango, will host the seminar. 

"Dr. Maria Onyango works on the biology underlying interactions between arboviruses (Zika virus), vector mosquitoes and the associated microbiome," Attardo said. 

Aedes aegypti Detected in Yolo County
The Sacramento-Yolo Mosquito and Vector Control District recently announced the detection of Aedes aegypti in Yolo County:  an adult female found Sept. 15 in a trap near East and Main streets, Winters, and an adult female found in in a trap at Pioneer Park near El Macero, Davis, on Sept. 30. 

Aedes aegypti, a day-biting mosquito originating from the forests of Uganda,  can transmit the Zika virus, yellow fever, dengue, and chikungunya. However, California has no documented cases of this species transmitting the Zika virus, dengue or chikungunya.

Attardo related that the first detection of Aedes aegypti in California occurred in 2013 and was described in these papers: 

• Metzger, M.E.; Hardstone Yoshimizu, M.; Padgett, K.A.; Hu, R.; Kramer, V.L. Detection and Establishment of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Mosquitoes in California, 2011-2015. J. Med. Entomol. 2017, 54, 533–543, doi:10.1093/jme/tjw237.
• Gloria-Soria, A.; Brown, J.E.; Kramer, V.; Hardstone Yoshimizu, M.; Powell, J.R. Origin of the dengue fever mosquito, Aedes aegypti, in California. PLoS Negl. Trop. Dis. 2014, 8, e3029, doi:10.1371/journal.pntd.0003029.

"Since then it has been determined that there have likely been at least two separate introductions of Aedes into California--possibly three but that requires additional study," Attardo says. "The result of this is that there are two genetically distinct populations of Aedes in California. One is based in Southern California in the Greater Los Angeles area as well as areas to the East, like Riverside and Coachella valleys. The second population is distributed throughout the Central Valley. These two populations are genetically distinct and we have developed a genetic assay to differentiate the two populations. We have been working with local abatement agencies (Winters, Sacramento/Yolo and Shasta counties) to test their collected mosquitoes to determine which population they resemble at the genetic level. Each year has shown Aedes aegypti spreading farther into parts of California where it has never been seen before."

• Pless, E.; Gloria-Soria, A.; Evans, B.R.; Kramer, V.; Bolling, B.G.; Tabachnick, W.J.; Powell, J.R. Multiple introductions of the dengue vector, Aedes aegypti, into California. PLoS Negl. Trop. Dis. 2017, 11, e0005718, doi:10.1371/journal.pntd.0005718.
• Lee, Y.; Schmidt, H.; Collier, T.C.; Conner, W.R.; Hanemaaijer, M.J.; Slatkin, M.; Marshall, J.M.; Chiu, J.C.; Smartt, C.T.; Lanzaro, G.C.; et al. Genome-wide divergence among invasive populations of Aedes aegypti in California. BMC Genomics 2019, 20, 204, doi:10.1186/s12864-019-5586-4.

 "We recently ran our genetic test on mosquitoes that we collected from two different sites in Citrus Heights (divided by Route 80) and actually found that the two groups appear to represent both the Greater Los Angeles and the Central Valley populations, with each group specific to one side or the other of Route 80," Attardo said. "This is unpublished data and we are continuing to process additional samples of collected Aedes to reinforce these findings and understand the dynamics of how these mosquitoes are spreading."  

Moving Throughout California
The data suggests "that both populations are moving throughout California and are possibly being facilitated by human activities," Attardo said. "Aedes aegypti which was originally a mosquito that developed in tree holes has evolved to be a very human centric mosquito that has learned to thrive in man-made breeding sites. This may be the key to their success and their ability to move so quickly throughout the state."

 Attardo emphasized that "these mosquitoes do not naturally carry these viruses and must acquire them by blood feeding on an infected person, successfully developing an infection and then biting another person. So far there have been no outbreaks of these diseases, but now that Aedes aegypti is here, the potential for an outbreak of dengue, Zika, chikungunya or yellow fever is a possibility. Infected people coming from countries where these viruses are endemic could serve to seed the viruses into Californian populations of Aedes which would obviously be a bad thing. The ongoing environmental changes resulting from climate change will likely allow these mosquitoes and others to move into previously uninhabitable areas and it is going to significantly change how we assess risk and management of mosquito-borne disease risks in the United States and around the world. California is just one example of this issue."

Aedes albopictus in California
Along with seven other scientists, Attardo and Onyango co-authored a research article in the Oct. 2nd edition of Frontiers in Microbiology on "Zika Virus Infection Results in Biochemical Changes Associated With RNA Editing, Inflammatory and Antiviral Responses in Aedes albopictus."

Aedes albopictus, also a day-biting mosquito, can transmit Zika and other infectious diseases. "The Zika virus infected more than 1 million people during an epidemic that began in 2015 in Brazil," according to this report, Invasive Mosquito Species Plunge Deeper Into California. The virus also can spread during sex.

Onyango holds two degrees from the University of Nairobi, Kenya: a bachelor of science degree in biochemistry and zoology and a master's degree in applied parasitology. She received her doctorate in veterinary entomology from Deakin University and Australian Animal Health Laboratory, Commonwealth Scientific and Industrial Research Organisation (CSIRO), and then completed postdoctoral training at the Yale School of Public Health, Department of Epidemiology of Microbial Diseases. 

Cooperative Extension specialist and assistant professor Ian Grettenberger coordinates the fall seminars. For any technical issues regarding the seminar, contact Grettenberger at imgrettenberger@ucdavis.edu 

Flies seem to be in the news a lot lately.

But have you ever looking closely at a common green bottle fly Lucilia sericata, also known as a blowfly?

Ever admired their brilliant metallic blue-green coloration? Ever thought about them as pollinators (they are sometimes!) but of course, that's not what they're known for.

They're known for their forensic, veterinary and medical importance. They are nature's recyclers when the females deposit their eggs in carrion.

But they're also beautiful. 

We captured these photos of a green bottle fly on a tropical milkweed, Asclepias curassavica, in our garden. The red and yellow blossoms contrasted nicely with the stunning fly coloration. Nature's art.

Indeed, flies are an integral part of the annual UC Davis Picnic Day (cancelled this year due to the COVID-19 pandemic and precautions). What's a picnic without flies?

Forensic entomologist Robert "Bob" Kimsey of the UC Davis Department of Entomology and Nematology always staffs a booth at Briggs Hall where he holds forth as "Dr. Death" with his microscope and specimens as he encourages--and fields--questions from the thousands of picnickers. (See Bugs at Briggs)

Also at Briggs Hall during the UC Davis Picnic Day, "Maggot Art," is extremely popular. The artists, mostly children and teens, dip a maggot into water-based, non-toxic paint and drop it onto a white piece of paper and let it crawl. The finished product often finds its way onto a refrigerator, inside a frame, or as as an unexpected gift to grandparents. Certainly it's a conversation piece.

Meanwhile, mark your calendar for April 17, 2021, the scheduled date of the next UC Davis Picnic Day. 

Dr. Bob, the flies, and the maggots will be waiting.  

Mark your calendar.

The Bohart Museum of Entomology at the University of California, Davis, is hosting a virtual open house dealing with alfalfa and rice.

Cooperative Extension agricultural specialist Ian Grettenberger, assistant professor, UC Davis Department of Entomology and Nematology, and his graduate student, Madison "Madi" Hendrick, will discuss the crops, the pests, and the natural enemies or beneficials at a virtual Facebook live session from 11 a.m. to noon, Thursday, Oct 22.

Yes, this applies to you. If you're a scientist or would-be scientist, you'll want to know more about these agricultural crops and the issues. If you're a consumer and like rice and ice cream (dairy cows eat alfalfa and milk comes from ice cream, you have a stake in this.  

The event, "The Good and the Bad: Insects and Other Arthropods in Agriculture, with a Focus on California Rice and Alfalfa," will be live-streamed on the UC Davis Bohart Museum of Entomology's Facebook page. (Link to Facebook live here). Grettenberger and Hendrick will present short talks and then field questions.  No personal Facebook account is required to join the session, which is free and open to the public.

"This is all about the arthropods, both the pests and beneficials that they study in the rice and alfalfa fields," said Tabatha Yang, education and outreach coordinator for the Bohart Museum of Entomology. "Most of the focus is on insects, but tadpole shrimp in rice fields also will be discussed." A virtual family craft activity is also planned.

"I will be discussing some of the insect (or arthropod) problems faced by growers of rice in California and some of the challenges in managing them, Grettenberger said. "In rice, some of the key arthropod pests are tadpole shrimp, which can turn what would have been a lush stand if rice into a poor stand with a lot of floating seedlings. Meanwhile, later in the year, armyworm caterpillars, the larvae of a moth, can chew on rice leaves and destroy plants. I'll discuss some of the ongoing work to better understand and manage these pests."

Grettenberg's fields of expertise include field and vegetable crops; integrated pest management; applied insect ecology, and biological control of pests. (See Spotlight on Ian Grettenberger.) Among his current grants:

• Protection of rice from invertebrate pests
• Insecticide resistant alfalfa weevils in the western United States: Quantifying the scope of resistance and implementing a plan to manage the threat​
• Management of key cotton arthropod pests with insecticides and acaricides, a proactive approach to prepare for the invasion of the tomato leafminer (Tuta absoluta)  into California
• Detection, biology and control of the exotic Swede midge (Contarinia nasturtii) for California cole crops
• Management of the western spotted and striped cucumber beetle in melon production
• Biological control of the bagrada bug
• Insecticide resistance monitoring and evaluation of efficacy of current chemical tactics for managing aphids and thrips in lettuce

Grettenberger joined the UC Davis Department of Entomology and Nematology in January 2019. Grettenberger, who fills the vacated position of Larry Godfrey (1956-2007), received his bachelor of science degree in biology, with an ecology, evolution and organismal emphasis (honors program) in 2009 from Western Washington University, Bellingham, Wash., and his doctorate in entomology in 2015 from Pennsylvania State University, State College, Pa. He served as a postdoctoral researcher in the Godfrey lab and later, the Frank Zalom lab, before accepting his current appointment of assistant Cooperative Extension specialist.

What sparked his interest in entomology? "I had biologist parents, and was drawn into entomology at a pretty young age," Grettenberger said. "I spent plenty of time looking in flowers and turning over logs looking for insects. Once I started thinking about going to graduate school for entomology, I decided to focus on the intersection of agricultural entomology and insect ecology. I wanted to work on applied issues in entomology."

Hendrick, a second-year graduate student in the Grettenberger lab, received her bachelor's degree in iInternational studies at North Carolina State University, and also spent a semester at Nagoya University in Japan (she minored in Japanese).

"I got my start in entomology completely by chance!," Hendrick related. "I needed a science credit and happened to pick a class called 'Insects and People.”' That class really helped me to reframe the way I thought about insects and appreciate what interesting little critters they are. Through that class, I was also able to get a job as an undergraduate assistant in an entomology lab. I worked in a specialty crops lab, where I developed interests in integrated pest management and invasive species. I now study insecticide resistance in the alfalfa weevil, and I'm excited to share what I've learned through this outreach event!"

Grettenberger, Yolo County Farm Advisor Rachael Freeman Long and Madi Hendrick recently wrote a piece in the UC Agricultural and Natural Resources (UC ANR) blog, Alfalfa and Forage News, "A (Virtual )Update on Worms, Weevils an Aphids in Alfalfa."

"This year, the Kearney Research and Extension Center Alfalfa and Forage Field Day went virtual," Grettenberger wrote. "Attendees did not get the chance to look out over lush fields of alfalfa or towering plantings of sorghum, but they get did an update on ongoing work in alfalfa and other forages. Our team put together a rapid-fire video to discuss what are typically the key insect pests in California alfalfa: summer worms, alfalfa weevils, and aphids."

The summer worms in alfalfa include the summer worms: Western yellowstriped armyworm, beet armyworm and alfalfa caterpillar. Another key pest is the alfalfa weevil. The trio also discussed  aphids and their natural enemies, including lady beetles, aka ladybugs).

Pests of rice include armyworms, aster leafhoppers, crayfish, rice leafminers, rice seed midges, rice water weevils and tadpole shrimp.

The Bohart Museum, directed by Lynn Kimsey, UC Davis professor of entomology, is located in Room 1124 of the Academic Surge Building on Crocker Lane, UC Davis campus, but is temporarily closed. The museum houses nearly eight million insect specimens; a live "petting zoo" of Madagascar hissing cockroaches, walking sticks and taranatulas; and a gift shop stocked with insect-themed T-shirts, books, posters, jewelry, candy and insect-collecting equipment.  (Gift items can now be shipped during the closure.)

More information on the Bohart Museum's virtual presentation is available on its website or by contacting Yang at tabyang@ucdavis.edu.

Resources: 

• Alfalfa and Forage News: A (Virtual) Update on Worms, Weevils and Aphids in Alfalfa (By Ian Grettenberger, Rachael Freeman Long and Madi Hendrick, Sept. 20, 2020) (See video on same page)
• Alfalfa and Forage News: Natural Enemies Are Important for Control of the Aphid Complex in Alfalfa--A Case Study (By Ian Grettenberger, Rachael Freeman Long, Daniel Putnam and Rob Wilson, April 7, 2020)
• UC Statewide Integrated Pest Management Program: How to Manage Pests of Alfalfa
• UC Statewide Integrated Pest Management Program: Insects and Other Pests of Rice 

Wanna piece of me? 

"Hey, Buckeye butterfly, you over there with chunks of a wing missing, yeah you, what happened?" 

"Well, it was like this. I was just fluttering around, looking for some good nectar, and a predator grabbed me. I don't know what it was. Maybe it was a praying mantis. Maybe it was a bird or a spider. I don't know. It happened so fast. But anyhow, I lost a couple of eyespots. Yes, it got a piece of me. But it didn't get all of me. I'm still here!"

It's the eyespots--or the missing eyespots--you notice first about the Buckeye butterfly, Junonia coenia.

The eyespots are thought to offer some kind of protection from predators.

"Predators think the eyespot is an eye on the head of its prey," according to the Conservancy of Southwest Florida website. "If the predator attacks the eyespot, it might chew off part of the butterfly's wing, but the butterfly's vital organs escape damage."

Butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, who has studied the butterfly populations of the Central Valley since 1972, writes about the Buckeye on his website, Art's Butterfly World:

"The Buckeye breeds on plants containing bitter iridoid glycosides, including plantains (Plantago, especially P. lanceolata), various Scrophulariaceae (especially Fluellin, Kickxia), and Lippia (Lippia or Phyla nodiflora). The spiny, black-and-white caterpillar has a bright orange head. Its behavior suggests its diet makes it virtually immune to vertebrate predation, but the pupa and adult are quite edible.

"Male Buckeyes are territorial perchers, usually on bare ground. Both sexes visit a great variety of flowers, from Heliotrope and Lippia to California Buckeye and Rabbitbrush! They often swarm over Coyotebrush (Baccharis) in autumn, especially the male plants.

And always, always, the Buckeyes need to keep an eye out for their predators.