- Author: Kathy Keatley Garvey
The paper appears in the current edition of Journal of Hydrobiologia.
“The water hyacinth, Eichhornia crassipes, is considered the world's most economically damaging aquatic weed,” said author Emily Bick, a UC Davis alumnus and a postdoctoral scholar at the University of Copenhagen, Denmark.
The free-floating perennial, native to the Amazon region of South America, is highly invasive throughout the world. It forms large floating mats when its roots and leaves intertwine. The aquatic weed is a major issue in the Sacramento-San Joaquin Delta in central California.
“This paper is the result of my first dissertation chapter,” said Bick, an agricultural entomologist who received both her master's degree (2017) and doctorate in entomology (2019) from UC Davis. “We aimed to determine if salinity was the reason N. bruchi was not effective at regulating the weed in the Sacramento-San Joaquin Delta compared with other worldwide locations. The results were not as clear cut as we hoped, as the study was limited in testing only adult weevils. However, the paper makes the case for including salinity as a screening variable for new biological control agents that are candidates for release in the Delta and other partially saline areas. Also, given the thoroughness of the experiments, there is at least one cool modeling paper to come out as a follow-up.”
All-Hands-on-Deck
The paper, titled “Effects of Salinity and Nutrients on Water Hyacinth and its Biological Control Agent, Neochetina bruchi, “was truly an all-hands-on-deck effort,” Bick said. "Specifically, a major project hurdle was the temperature in Davis."
She related that the greenhouse experiments on water hyacinth “weren't producing consistent results due to the high variation—and high heat--in water temperature.” So fellow scientists Danny Klittich, then a UC Davis doctoral student in entomology with the Michael Parrella laboratory, and Bob Starnes, then UC Davis senior superintendent of agriculture, built a giant water bath out of a leftover evaporative cooler from the Michael Parrella lab.
Klittich is now the California Central Coast Agronomist with Redox Chemicals and chief executive officer and founder at HowToGrowRoses.org. Starnes is vice president of agriculture for UAV-IQ (Unmanned Aerial Vehicle Intelligence.
In addition to Klittich and Starnes, other co-authors are UC Davis postdoctoral scholar Elvira deLange of the Christian Nansen lab; then doctoral student Cindy Kron of the Frank Zalom laboratory; and undergraduate students Jessie Liu and Derrick Nguyen. Kron, now with UC Cooperative Extension, is the North Coast Area Integrated Pest Management (IPM) Advisor, serving Sonoma, Napa, Mendocino and Lake counties.
The Abstract
“Water hyacinth, Eichhornia crassipes (Mart.) Solms (Commelinales: Pontederiaceae), is an important aquatic weed worldwide. Previous studies demonstrate that releases of Neochetina bruchi Hustache (Coleoptera: Curculionidae) provide biological control in many locations, but not all. Notably, N. bruchi were unsuccessful at regulating water hyacinth in tidal brackish waters. Abiotic factors, including salinity and nutrients, affect water hyacinth growth, but little is known about the impact of salinity on weevil survival. We hypothesized that N. bruchi has a relatively low salinity tolerance. In a mesocosm experiment, we assessed weed growth in response to a range of salinity and nutrient concentrations. In a laboratory, we assessed adult N. bruchi mortality in response to various salinity concentrations. Results indicate that increasing nutrient concentration increases weed growth. When both nutrient and salinity levels were varied, nutrients increased leaf count, but not biomass, while salinity reduced growth and increased mortality. Increasing salinity concentrations increased adult weevil mortality; required concentrations were higher than that for weeds. Thus, these results did not provide support for the suggested hypothesis. Potential effects of salinity via other exposures to weevils need to be investigated. Elucidating abiotic factors important for weed growth and weevil survival may increase effectiveness of water hyacinth management practices.”
The water hyacinth was introduced in California in 1904. Scientists trace its history in the United States back to 1884 at the New Orleans Exposition. “Samples are said to have been given to fair-goers, and within 4 years, coastal fresh waters were infested from Texas to Alabama. By 1972, the infestation in Florida was estimated to be 200,000 acres,” according to Cornell University. “Large, floating mats of waterhyacinth obstruct navigation, clog irrigation works, disrupt the natural ecology of wetlands in many ways, exacerbate mosquito problems, and are costly to the tourism and recreation industries.”
Two biocontrol agents, weevils N. eichhorniae and N. bruchi, natives of Argentina, and surrounding areas in South America, were released in 1972 and 1974, respectively.
- Author: Kathy Keatley Garvey
Ever seen a back-lit monarch butterfly?
It's like a stained-glass window in a centuries-old steepled church where you cannot see the ugliness of the world, but its beauty.
Monarchs are like that. Those iconic butterflies excite, inspire and transform you, just like stained glass windows.
We captured these images at dusk of a monarch fluttering around an aphid-infested milkweed, a tropical milkweed, Asclepias curassavica, on Aug. 7 in Vacaville, Calif.
The orange butterfly was nothing but a blur until we stopped the action (1/4000 of a second) with a 200mm macro lens mounted on a Nikon D500.
The beauty (the monarch) eclipsed the beast (oleander aphids) in a moment of time.
- Author: Kathy Keatley Garvey
Unless it encounters a predator or parasitoid or another life-threatening factor, the egg will usually hatch 3 to 4 days after Mama Monarch deposits it beneath a milkweed leaf. As you know, monarchs lay their eggs only on milkweed, their host plant.
If you enjoy macro photography, it's a delight to photograph an egg with a highly specialized lens like the Canon MPE-65mm lens. Or you can observe the tiny egg with a magnifying glass or microscope.
How do you rear it?
Naturalist Greg Kareofelas, an associate of the Bohart Museum of Entomology at the University of California, does it this way:
"I put a single egg on its leaf in a small salsa container (the little plastic ones you would get at a Mexican restaurant). I take a square of toilet paper and fold it into a small square (3/4 of inch), dampen it and squeeze it so it is not sopping wet, just damp, and set the leaf and egg on the top. Put the lid tightly on the container. This keeps a level of moisture in the container. I check the containers daily, changing the toilet paper square to keep from molding."
"I raise the larva in that container until it gets big enough to move to a larger container. As long as you pay attention and check them often to make sure there is no mold or such, I have raised many this way successfully. The tight lid and slight moisture keeps the food plant fresher."
"You don't want loose water in the container, just enough so it is not dry," he says.
Among the many species of butterflies he's reared: the dogface butterfly or California state insect, Zerene eurydice; the Colias behrii, the Behr's sulphur or Sierra green sulfur; and the monarch, Danaus plexippus.
When our family rears monarchs, we usually begin with the caterpillars instead of the eggs. They're easier to find and collect. However, if you see a monarch laying her eggs, you know exactly where to look! Last weekend we watched a monarch deposit her eggs on our tropical milkweed, Asclepias curassavica, and our narrow-leaf milkweed, Asclepias fascicularis. We collected three eggs from the fascicularis and let the others be.
An adult monarch can lay about 400 eggs in her lifetime, Kareofelas says. Only a few survive due to predators and parasitoids and other factors. The major parasitoid in our garden is the tachinid fly which lays its eggs in or on the host or deposits its eggs on the milkweed leaves.
"If you start with the egg, the chance of it being parasitized is really small," says Kareofelas, who has been rearing butterflies most of his life, and especially for the last 15 years.
When the egg hatches into a larva or caterpillar, the 'cat will eat the eggshell first and then go about munching the milkweed. When it gets bigger, it's time to move it into a larger container. You must keep the milkweed fresh, as it can dry out quickly. Kareofelas likes to use water-filled floral tubes and dampened packing foam to keep the leaves/stems moist.
Our family's procedure to rear caterpillars: fill a heavy, wide-bottomed, narrow-necked tequila bottle with water, add sprigs of milkweed and the 'cats, and place in a zippered, net butterfly habitat. We place ours in our kitchen, a tachnid-free environment! Those tachnids can be sneaky! Also, replenish your milkweed and water daily, and remove the frass (excreta) daily.
It's a joy watching the complete metamorphosis, about a 30-day development from egg to larva to chrysalis to adult. The larval stage or caterpillar stage usually lasts 10 to 14 days, during which time the caterpillar will go through five instars (when it molts or sheds it skin). The 'cat will then form a "j" and pupate. The chrysalis stage lasts about 10 to 14 days, and voila! The familiar monarch icon ecloses and it's released back into the garden to start the cycle all over again.
Yes, it's a joy to watch them. But it's not a joy watching a tachnid-infested monarch caterpillar or a chrysalis. (We'd rather the tachnids lay their eggs in such pests as cabbage loopers or tomato hornworms.)
A good place to see butterfly specimens from all over the world is the Bohart Museum of Entomology (now temporarily closed due to the COVID-19 pandemic. Of the nearly eight million specimens in the Bohart, some 500,000 are in the Lepidoptera collection, curated by entomologist Jeff Smith. He and Kareofelas display and discuss the Lepidopterans during the open houses. In the meantime, watch the moth-butterfly videos on the Bohart Museum page.)
- Author: Kathy Keatley Garvey
The award, which includes a certificate and a cash prize, is presented by ESA's Systematics, Evolution and Biodiversity Section.
Boudinot, who received his doctorate in entomology in June, studied with major professor Phil Ward of the UC Davis Department of Entomology andNematology. His dissertation: "Systematic and Evolutionary Morphology: Case Studies on Formicidae, Mesozoic Aculeata, and Hexapodan Genitalia.”
The Snodgrass Award recognizes outstanding research by a PhD student who has completed a research thesis or dissertation in arthropod morphology, systematics, taxonomy, or evolution. Nominees are scored on honors, awards, achievements and recognition; recommendations of professors and advisors; grantsmanship, publications, creativity and innovation of thesis or dissertation; and contribution to morphology.
Boudinot is the second UC Davis-affiliated entomologist to receive the honor in its 28-year history. Jessica Gillung of the Lynn Kimsey lab, Bohart Museum of Entomology, won the award in 2019.
Snodgrass (1875-1962), a leader in insect morphology, is known for his 76 scientific articles and six books, including Insects, Their Ways and Means of Living (1930) and the book considered to be his crowning achievement, the Principles of Insect Morphology (1935).
Boudinot has them all. “Principles of Insect Morphology and the Anatomy of the Honey Bee were the foundation of my studies,” he said. “I have both, plus his Textbook of Arthropod Morphology and Insects, Their Ways and Means of Living on my desk in the lab.”
He earlier received the prestigious Alexander von Humboldt Research Fellowship to do research on evolutionary and comparative anatomy in Jena, Germany. He will locate to Germany in early 2021 for the two-year fellowship, after completing intensive language studies.
“I am a morphologist because of Robert Evans Snodgrass,” Boudinot wrote in his application. “Although I have had pressure from my earliest undergraduate to become a molecular systematist, it was my chance encounter with Snodgrass's Principles of Insect Morphology late one night in the college library that set the course of my career. I had struggled for years at that point to understand the biodiversity of insects and to untangle the deep morass of arcane terminology, but my vision was illuminated by the conceptual clarity, linguistic simplicity, and exceptional engravings of the Principles. This work continues to hold special dominion over my thinking, as it is through the principle of mechanical function for explaining comparative anatomical observations that I have come to my present understanding of systematic and evolutionary morphology.”
Boudinot wrote that his “career objective, in brief, is to resolve the morphological evolution of insects through the synthesis traditional morphology, as represented by Snodgrass, with recent trends in digital anatomy and bioinformatics. I envision a future wherein students rely not on Borror & Delong, a holdover from Comstock's 19thCentury manual, but rather learn about insect structure, function, classification, and evolution through manipulation of three- and four-dimensional digital anatomical models, substantiated via manual curation and dissection. I want students to see for themselves what I have understood through the study of Snodgrass's work, balanced by contemporary research: The origin of the Arthropoda and morphological transformation through geological time to the resplendent, and endangered, diversity of today.
“In sum, my identity as an entomologist, and as a scientist more broadly, is due to the insights on the language and phenomenology of morphological evolution I gained from the oeuvre of Snodgrass. Without these works, I would probably still be a botanist.”
John Henry Comstock Award
Highly honored for his academics, leadership, public service activities, professional activities and publications while at UC Davis, Boudinot received the 2019 John Henry Comstock Award, the top graduate student award given by ESA's Pacific Branch. The branch encompasses 11 Western states, U.S. territories, and parts of Canada and Mexico.
In the Comstock award application, Steve Nadler, professor and chair of the Department of Entomology and Nematology, described Boudinot as “A highly respected scientist, teacher and leader with a keen intellect, unbridled enthusiasm, and an incredible penchant for public service.” Boudinot maintained a 4.00 grade point average and published 18 peer-reviewed publications on insect systematics, some landmark or groundbreaking work.
His most recent publications: one on Cretaceous Strepsiptera in Cladistics and the other on the iron maiden ants in Myrmecological News ("Two New Iron Maiden Ants from Burmese Amber (Hymenoptera:
Formicidae: †Zigrasimeciini").
Boudinot received multiple “President's Prize” awards for his research presentations at national ESA meetings. He organized the ESA symposium, “Evolutionary and Phylogenetic Morphology,” at the 2018 meeting in Vancouver, B.C. , and delivered a presentation on “Male Ants: Past, Present and Prospects” at the 2016 International Congress of Entomology meeting in Orlando, Fla.
Boudinot served on—and anchored—three of the UC Davis Linnaean Games teams that won national or international ESA championships. The Linnaean Games, now known as the Entomology Games, are a lively question-and-answer, college bowl-style competitions on entomological facts played between university-sponsored student teams.
Brendon served as president of the UC Davis Entomology Graduate Student Association from 2006 to 2019, and co-chaired the department's UC Davis Picnic Day celebration (with forensic entomologist Robert Kimsey) for three years.
Before enrolling in graduate school program at UC Davis in 2014, Brendon received his bachelor's degree in entomology in 2012 from The Evergreen State College, Olympia, Wash. Professor John T. Longino served as his mentor.
who studied with major professor Phil Ward of the UC Davis Department of Entomology and Nematology, is the second UC Davis-affiliated entomologist to receive the honor in its 28-year history. Jessica Gillung of the Lynn Kimsey lab, Bohart Museum of Entomology, won the award in 2019.
Snodgrass (1875-1962), a leader in insect morphology, is known for his 76 scientific articles and six books, including Insects, Their Ways and Means of Living (1930) and the book considered to be his crowning achievement, the Principles of Insect Morphology (1935).
Boudinot has them all. “Principles of Insect Morphology and the Anatomy of the Honey Bee were the foundation of my studies,” he said. “I have both, plus his Textbook of Arthropod Morphology and Insects, Their Ways and Means of Living on my desk in the lab.”
The Snodgrass Award, which includes a certificate and cash prize, recognizes outstanding research by a PhD student who has completed a research thesis or dissertation in arthropod morphology, systematics, taxonomy, or evolution. Nominees are scored on honors, awards, achievements and recognition; recommendations of professors and advisors; grantsmanship, publications, creativity and innovation of thesis or dissertation; and contribution to morphology.
Boudinot's dissertation: “Systematic and Evolutionary Morphology: Case Studies on Formicidae, Mesozoic Aculeata, and Hexapodan Genitalia.”
He earlier received the prestigious Alexander von Humboldt Research Fellowship to do research on evolutionary and comparative anatomy in Jena, Germany. He will locate to Germany in early 2021 for the two-year fellowship, after completing intensive language studies.
'I Am a Morphologist Because of Robert Evans Snodgrass'
“I am a morphologist because of Robert Evans Snodgrass,” Boudinot wrote in his application. “Although I have had pressure from my earliest undergraduate to become a molecular systematist, it was my chance encounter with Snodgrass's Principles of Insect Morphology late one night in the college library that set the course of my career. I had struggled for years at that point to understand the biodiversity of insects and to untangle the deep morass of arcane terminology, but my vision was illuminated by the conceptual clarity, linguistic simplicity, and exceptional engravings of the Principles. This work continues to hold special dominion over my thinking, as it is through the principle of mechanical function for explaining comparative anatomical observations that I have come to my present understanding of systematic and evolutionary morphology.”
Boudinot wrote that his “career objective, in brief, is to resolve the morphological evolution of insects through the synthesis traditional morphology, as represented by Snodgrass, with recent trends in digital anatomy and bioinformatics. I envision a future wherein students rely not on Borror & Delong, a holdover from Comstock's 19thCentury manual, but rather learn about insect structure, function, classification, and evolution through manipulation of three- and four-dimensional digital anatomical models, substantiated via manual curation and dissection. I want students to see for themselves what I have understood through the study of Snodgrass's work, balanced by contemporary research: The origin of the Arthropoda and morphological transformation through geological time to the resplendent, and endangered, diversity of today.
“In sum, my identity as an entomologist, and as a scientist more broadly, is due to the insights on the language and phenomenology of morphological evolution I gained from the oeuvre of Snodgrass. Without these works, I would probably still be a botanist.”
Boudinot's research interests include the origin and evolution of complex phenotypic systems from the perspective of phylogenetic systematics, including molecular and paleontological evidence. Specializing on morphological identity and evolutionary transformation, the skeletomuscular system of Arthropoda, with emphasis on the male genitalia of Hexapoda and systematics of the Hymenoptera, particularly the Formicidae.
John Henry Comstock Award
Highly honored for his academics, leadership, public service activities, professional activities and publications while at UC Davis, Boudinot received the 2019 John Henry Comstock Award, the top graduate student award given by ESA's Pacific Branch. The branch encompasses 11 Western states, U.S. territories, and parts of Canada and Mexico.
In the Comstock award application, Steve Nadler, professor and chair of the Department of Entomology and Nematology, described Boudinot as “A highly respected scientist, teacher and leader with a keen intellect, unbridled enthusiasm, and an incredible penchant for public service.” Boudinot maintained a 4.00 grade point average and published 18 peer-reviewed publications on insect systematics, some landmark or groundbreaking work.
His most recent publications: one on Cretaceous Strepsiptera in Cladistics and the other on the iron maiden ants in Myrmecological News ("Two New Iron Maiden Ants from Burmese Amber (Hymenoptera:
Formicidae: †Zigrasimeciini").
Boudinot received multiple “President's Prize” awards for his research presentations at national ESA meetings. He organized the ESA symposium, “Evolutionary and Phylogenetic Morphology,” at the 2018 meeting in Vancouver, B.C. , and delivered a presentation on “Male Ants: Past, Present and Prospects” at the 2016 International Congress of Entomology meeting in Orlando, Fla.
Boudinot served on—and anchored—three of the UC Davis Linnaean Games teams that won national or international ESA championships. The Linnaean Games, now known as the Entomology Games, are a lively question-and-answer, college bowl-style competitions on entomological facts played between university-sponsored student teams.
Brendon served as president of the UC Davis Entomology Graduate Student Association from 2006 to 2019, and co-chaired the department's UC Davis Picnic Day celebration (with forensic entomologist Robert Kimsey) for three years.
Before enrolling in graduate school program at UC Davis in 2014, Brendon received his bachelor's degree in entomology in 2012 from The Evergreen State College, Olympia, Wash. Professor John T. Longino served as his mentor.
- Author: Kathy Keatley Garvey
Remember the massive media frenzy earlier this year when "the murder hornet" became a household word? The media labeled it that, but let's call it AGH. It's a hornet, not some weaponized insect with super powers that belongs in a B-rated movie seen at a Saturday matinee. Drop the drink! Hold the popcorn!
The peer-reviewed publication is the work of two former UC Davis entomologists now with WSU: honey bee geneticist-researcher Susan Cobey, research associate, Department of Entomology, and Timothy Lawrence, associate professor and Island County Extension director (they are a husband-wife team), along with Michael Jensen, associate professor and Pend Oreille County Extension director.
The first four paragraphs zero in on what this is all about:
"The Asian giant hornet (AGH) or Japanese giant hornet, Vespa mandarinia, recently found in British Columbia, Canada, (B. C. Ministry of Agriculture 2019) and in Washington State (McGann 2019), poses a significant threat to European honey bee (EHB), Apis mellifera, colonies and is a public health issue. The AGH is the world's largest species of hornet (Figure 1; Ono et al. 2003), native to temperate and tropical low mountains and forests of eastern Asia (Matsuura 1991). It appears the hornet is well adapted to conditions in the Pacific Northwest.
"If this hornet becomes established, it will have a severe and damaging impact on the honey bee population, the beekeeping industry, the environment, public health, and the economy. It is critical that we identify, trap, and attempt to eliminate this new pest before it becomes established and widespread. Attempts to contain the spread and eradication of this invasive insect will be most effective by trapping queens during early spring before their nests become established. Another strategy is to locate and destroy nests prior to development of virgin queens and drones in the late summer and fall.
"It is critical that surveying and trapping occur before the fall reproductive and dispersal phase of the hornet. Beekeepers in the field are a crucial line of defense in locating, identifying, and trapping the hornets. Yet, everyone should be on the lookout and report any sightings to local authorities and the Washington State Department of Agriculture.
"Here, we will cover how the AGH will impact the honey bee, give the reader a better understanding of the hornet, outline precautions to take, and first aid if attacked by the hornet."
The fact sheet provides crucial information, including what the public and beekeepers need to know, how to trap the hornets, where to report sightings, and information about the life cycle, the stinger, avoidance, and first aid. It details the public health issue and defines "What is a hornet?"
We've heard folks argue that AGH is a "hornet, not a wasp." Noted hymenopterist Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis, points out that hornets ARE wasps.
WSU Extension defines a hornet this way:
"A hornet is simply a large wasp. Generally, wasps of the class or genus known as Vespa are considered hornets. Interestingly, there are no true hornets (Vespa) native to North America. The European hornet (Vespa crabro) is well established in much of the eastern half of the United States. The European hornet is not a major threat to honey bees."
"Hornets are part of a large order of insects known as Hymenoptera that include bees, wasps, ants, and sawflies. Worldwide, there are more than 115,000 species belonging to the order Hymenoptera (Hunt and Toth 2017). Most of this group of insects are beneficial for pollination and pest control. There are two types of hornets, solitary and social (Lee et al. 2016). Solitary hornets hunt various insects and spiders. Their 'stinger' is primarily used to paralyze their prey. They often lay an egg on the immobilized victim, and when the egg hatches, the larvae consume the still-living host. Solitary wasps generally do not sting humans and usually are not aggressive unless provoked."
"Social wasps, on the other hand, do use their stingers to defend their nests and can be very aggressive and will readily sting. The most common social wasp in the United States is the yellowjacket. The four most common yellowjacket species in Washington are the western yellowjacket (Paravespula pensylvanica), the common yellowjacket (Paravespula vulgaris), the aerial yellowjacket (Dolichovespula arenaria), and the German yellowjacket (Paravespula germanica) (Berry and Mooney 1998; Landolt and Antonelli 2003)."
"The recently introduced Asian giant hornet (AGH) is also a social wasp. When foraging for food in spring, the AGH ;is not highly aggressive—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."
AGH appeared in the news last month when the Washington State Department of Agriculture announced it had trapped aVespa mandarinia near Birch Bay in Whatcom County. It was trapped July 14 and identified during processing on July 29. "This was the first hornet to be detected in a trap, rather than found in the environment as the state's five previous confirmed sightings were," according to the news release.
"Because the number of Asian giant hornet workers increases as a colony develops, residents should be most likely to see an Asian giant hornet in August and September," the news release related. "If you think you have seen one, report it at agr.wa.gov/hornets. Provide as much detail as you can about what you saw and where. Also, include a photo if you can safely obtain one, and if you come across a dead specimen keep it for potential testing. You can visit WSDA's website at agr.wa.gov/hornets to learn more about Asian giant hornets. You can also submit questions the WSDA Pest Program at hornets@agr.wa.gov or 1-800-443-6684."
At least we never saw a 64-point bold, all-capped, World War II-sized newspaper headline that screamed "MURDER HORNET TRAPPED!"
But some of the misidentifications of Vespa mandarinia flowing in are incredible. Check out Stephane de Greef's Facebook page on "Is This a Murder Hornet?" The latest one spotlighted is a...wait for it...beetle.
