If you grow citrus, you've probably been “introduced” to the introduced European earwig, Forficula auricularia, the most common of the earwig species infesting the fruit here in California.  

 “They feed mostly at night and hide during the day,” according to the UC Statewide Integrated Pest Management Program. They hide in the bark crevices, mulch, and “protected compact plant parts such as dried, curled leaves, and under trunk wraps.” 

“Earwigs feed on dead and living insects and insect eggs and on succulent plant parts, UC IPM says. "Earwig nymphs and adults will climb trees and feed on flower buds, leaves, and fruit of trees during the spring flush months (March through May). Nymphs tend to feed on plant material more than adults...Earwigs can be very problematic on young trees with trunk wraps or cardboard guards, in which they reside. They climb the trees and feed on the new leaves. Large numbers of earwigs can defoliate trees.”

Enter ecological pest management specialist Hanna Kahl, who recently received her doctorate in entomology from UC Davis, studying with UC Davis distinguished professor Jay Rosenheim. She'll present her exit seminar on “Herbivory of Citrus Fruit by European Earwigs in California” at 4:10 p.m, Wednesday, Sept. 29 in Room 122 of Briggs Hall. This in-person will be the first of the UC Davis Department of Entomology and Nematology's fall seminars. Many of the others will be virtual. 

“Growers and pest control advisors in California suspect that European earwigs (Forficula auricularia) damage young citrus fruit,” Kahl writes in her abstract. “However, very little is known about herbivory by earwigs on citrus fruit. Our work details characteristics of herbivory by earwigs on citrus fruit and the use of sticky and pesticide barriers to manage earwigs and other citrus pests.” 

Kahl, awarded her doctorate in August, focused her research on understanding the role of European earwigs in California citrus; developing a whole systems approach to manage earwigs and other citrus pests; and feeding preferences of fort-tailed bush katydids and citrus thrips on California citrus. 

Kahl is now an ecological pest management specialist at Community Alliance with Family Farmers, Davis. She leads projects and extension efforts on sustainable pest management tactics. 

She received an ongoing grant in 2019 from the Citrus Research Board on “Characterizing Earwig Damage to Citrus Fruits, and Damage Prevention using Trunk Barrier Treatment.” She also received a National Science Foundation Graduate Research Fellowship, awarded in 2017, and a 2018-19 Keller Pathways Fellowship (for entrepreneurship) from the University of California.

Active in both the Entomological Society of America and the Ecological Society of America, she won first place in the Student 15-Minute Paper Competition at the 2016 meeting of the International Congress of Entomology; and second place in the Student 10-Minute Paper Competition at the 2019 meeting of the Entomological Society of America (ESA). She served on the Eastern Branch team that won second place in the ESA's 2016 Linnaean Games, now called the Entomology Games. She co-organized  a seminar, “Agroecology with Communities: Cross-Disciplinary Collaborations Between Ecology, Agriculture and Social Science,” for the Ecological Society of America at its 2019 meeting. 

Kahl received her bachelor's degree in biology from Whitman College, Walla Walla; her master's degree in entomology from the University of Maryland, College Park. At Whitman College, she researched the effects of reservoirs as habitat barriers on song sharing of the birds, dickcissels. At the University of Maryland,  she focused her research topics on effects of red clover as a living mulch cover crop on arthropod herbivores, natural enemies, pollination and yield in cucumber; (2) consumptive and non-consumptive effects of wolf spiders on cucumber beetles and (3) effects of red clover living mulch on greenhouse gas emissions.  She studied abroad in a six-month School for International Training program in Jaipur, Rajasthan, India in 2010. Her research topic: Village dairy production in Haryana and Orissa.

Her current activities include being the chapter leader for Women in Data (WID), Sacramento. 

Kahl's exit seminar will be recorded for later viewing, according to seminar coordinator Shahid Siddique (ssiddique@ucdavis.edu), a nematologist and assistant professor, UC Davis Department of Entomology and Nematology. The seminars take place every Wednesday at 4:10 p.m. Many are virtual.

They knew the answer. 

"A worker honey bee has how many pairs of wax glands on its abdomen?"

That would be four, answered the UC Davis Entomology Team did at the Entomological Society of America's Virtual Entomology Games, a college-bowl type of competition formerly known as the Linnaean Games. 

Doctoral students Jill Oberski, Zachary Griebenow and Hannah Kahl of the UC Davis Department of Entomology and Nematology teamed to compete in Games, a fun and lively event but this year it went virtual due to COVID-19 pandemic precautions. 

Oberski and Griebenow are both fourth-year doctoral students in the Phil Ward lab, while Kahl, a member of the Jay Rosenheim lab, is currently a third-year doctoral student who will begin her fourth year in January. 

The UC Davis team won its preliminary round and then entered the highly competitive finals, placing 11th. Alabama's Auburn University edged the Boiler Bugs of Purdue to win the championship. 

 

“This  year's format was significantly different from the past since it was held virtually,” said Joe Rominiecki, manager of communications for the Entomological Society of America (ESA). “A  preliminary round was held in early November online via WikiQuiz, and then the finals, with 14 teams total, took place live, broadcast via Zoom, on Monday night, Nov. 16. But rather than a head-to-head competition as in the past, all 14 teams competed at once, answering the same questions--four rounds of 10 questions, plus a tiebreaker question.” 

The champions, from Auburn University's Department of Entomology and Plant Pathology, answered 27 of the 40 questions correctly, tying with the Boiler Bugs of Purdue, “but Auburn had the closest answer for the tiebreaker question,” Rominiecki said. 

In the Entomology Games, teams of two to four students test their entomological knowledge by answering questions drawn from all disciplines of insect science: behavior and ecology, biological control, entomology in culture, integrated pest management (IPM) and insect/plant interactions, medical and veterinary entomology, biochemistry and toxicology economic entomology, history of entomology, morphology and physiology, and systematics and evolution. 

In this year's event, the games were divided into four rounds of 10 questions each. All teams competed to answer the same sets of questions. Each question was worth one point, with 40 being the best possible score. 

ESA did not record the Games this year, as the event itself “was mostly just a recitation of the questions, without the more lively 'buzzing in' format of the live event,” Rominiecki related.

“All in all, we were pleased with how the Entomology Games went this year, in an entirely new format," he said. "Our organizers worked hard in just a few short months to create a virtual version of the Games, and it was great to have teams from all over the country participating as usual, despite the new circumstances. We look forward to returning to an in-person event in the future, of course, but the 2020 virtual edition will be a memorable one. Congratulations to Auburn on their victory, and kudos to all the teams who participated!”

Some of the questions the UC Davis team answered correctly (answers below):

1. Keye Luke, Jay Chou, and Bruce Lee have all portrayed Kato, the crimefighting partner of what fictional vigilante?
2. What is the full scientific name (genus and species) of the bacterium classified by IRAC as a microbial disruptor of insect midgut membranes?
3. "Yoke-winged" is the literal translation of the name of what insect suborder, which can be distinguished from other members of its order by the presence of caudal gills on the aquatic immatures?
4. Although this year's festivities were postponed due to COVID-19, the small town of Point Pleasant, West Virginia, normally hosts an annual festival that commemorates the 1966 sightings of what paranormal figure?
5. A widely-publicized 2017 study reported a 75 percent decline in insect biomass over the past 27 years. This study was conducted across 63 protected natural areas in what European country?
6. What striking form of structural coloration involves color changes based on the angle of the observer, and was recently shown to help jewel beetles camouflage in order to avoid bird predation?
7. These specialty loaves of bread are labeled "kuwagata," which is a Japanese word that refers to insects in what family?
8. "Stimulo-deterrent diversion" was one of the earlier names for what IPM strategy that uses volatile cues from both repellent and attractant plants to reduce damage from insect pests?
9. The megalopteran family Corydalidae is divided into two clades: Corydalinae (aka dobsonflies) and what other subfamily, whose members are commonly known as fishflies?
10. Bombykol and bombykal are components of a sex pheromone emitted by certain females in what insect order?
11. What term refers to a parasitoid that halts the development of its host shortly after the initial parasitization?
12. Paederus dermatitis, also known as whiplash dermatitis, is a type of skin irritation caused by contact with the hemolymph of certain species in what insect family?
13. What type of semiochemical benefits the receiver and harms the emitter?
14. What sixteen-letter adjective is most commonly used to describe fungi and nematodes that can potentially act as biological control agents of insect pests?
15. Of the three types of lobes typically found in an insect brain, which lobe innervates the labrum and foregut?
16. A 2020 Ig Nobel Prize was awarded to Richard Vetter for collecting evidence that many entomologists exhibit what psychological condition? This condition is also the title of a movie that won the 1990 Saturn Award for Best Horror Film.
17. What twelve-letter term was coined by entomologist Willi Hennig to refer to a derived character that is shared between multiple species and their most recent common ancestor?
18. The first sighting of emerald ash borer in North America occurred in 2002, when it was discovered attacking ash trees in Ontario, Canada and what U.S. state?

Answers:

1. Green Hornet
2. Bacillus thuringiensis
3. Zygoptera
4. Mothman
5. Germany
6. Iridescence
7. Lucanidae
8. Push pull
9. Chauliodinae
10. Lepidoptera
11. Idiobiont
12. Staphylinidae
13. Kairomone
14. Entomopathogenic
15. Tritocerebrum
16. Arachnophobia
17. Synapomorphy
18. Michigan

The tiebreaker question? It dealt with the number of Far Side comics referencing insects. The question: "Gary Larson is known for using insects as a source of humor in his acclaimed comic strip 'The Far Side.' A survey of 4,300 'Far Side' comics revealed that exactly how many contained some sort of entomological reference?" Answer: 359. 

Over the last few years, UC Davis teams have won the national championship three times in the fun and lively competitions. (See Bug Squad blog) 

"Hopefully, we can be back onstage in person next year," said Oberski. 

Two doctoral students in the UC Department of Entomology and Nematology excelled in their research presentations at the recent meeting of the Entomological Society of America in St. Louis, Mo.

Jill Oberski, who studies with professor and ant specialist Phil Ward,  submitted an infographic titled “Discovery and Diversity: The Importance of Systematic Entomology in Today's World in the Systems,” in the Evolution and Biodiversity (SysEB) Section and won a second-place award.

Oberski also won a second-place award for her dissertation research “Unraveling the Phylogeny and Biogeography of Dorymyrmex, a New World Amphitropical Disjunct” in the category SysEB: Phylogenetics 2. 

Hanna Kahl, who studies with professor and insect ecologist Jay Rosenheim, won a second-place award for her "Characteristics of European Earwig (Forficula auricularia) Damage on Citrus Fruit," entered in the  Plant-Insect Ecosystems (P-IE), Integrated Pest Management Field Crops 5 Section.

The research presentations are highly competitive. "Entomology 2019 was an exciting four days filled with 236 scientific sessions featuring 2,205 oral and 680 poster presentations with 3,653 attendees from 61 different countries," an ESA spokesman said. "This year was a record setting event with 1,150 students attending!"

Those in the (SysEB) Section study insect anatomy, classification, and history. The section focuses on systematics, evolution, and biodiversity, but it also includes morphology, ecology, population dynamics, genetics, phylogeny, nomenclature, biogeography, zoology, and other specialties. 

Those in the PI-E section deal with insect interactions with plants. Topics include behavioral, ecological, and evolutionary relationships in natural landscapes, as well as integrated pest management (IPM) in agriculture, horticulture, forests, and lawn and garden. This includes such aspects as crop protection, host-plant response, plant pathology/vectors, pollination, biological control and microbial control.

Both Oberski and Kahl also served as members of the UC Linnaean Games Team, comprised of UC Davis and UC Berkeley graduate students,  that competed with other university teams throughout the nation. The Linnaean Games, launched in 1983, are lively question-and-answer, college bowl-style competitions on entomological facts.  The teams score points by correctly answering random questions.

Members of the national award-winning University of California Linnaean Games Team competed in the Linnaean Games at the recent Entomological Society of America (ESA) meeting in St. Louis, Mo., but this time they didn't take home a trophy.

The team was eliminated in the first round. Some logistics issues--microphone mishaps and difficulty hearing the questions (issues later resolved)--complicated the session.

Previously the UC team won three national championships. This year the University of Florida team triumphed.

The Linnaean Games, launched in 1983, are lively question-and-answer, college bowl-style competitions on entomological facts and played by winners of the ESA branch competitions. The teams score points by correctly answering random questions.

The 2019 UC team, captained by Ralph Washington Jr., a UC Berkeley public policy graduate student who received his bachelor's degree in entomology at UC Davis, included five UC Davis doctoral students in entomology:  Brendon Boudinot, Zachary Griebenow and Jill Oberski, all of the Phil Ward lab, UC Davis Department of Entomology and Nematology; and alternates Miles Dakin of the Christian Nansen lab and Hanna Kahl of the Jay Rosenheim lab.

Washington captained all four recent teams, and Boudinot helped anchor all of them.

The record:

• 2018: UC won the national championship (link to news story) in Vancouver, B.C., defeating Texas A&M Graduates, with Washington captaining the team and joined by Boudinot, Oberski and Griebenow, and Emily Bick (who received her doctorate this year) of the Christian Nansen lab. (No video of the championship round)
• 2017: The UC team did not compete. (Texas A&M won the national championship; see championship round on YouTube)
• 2016: UC won the national and international championships at the University of Florida, at the joint and international meeting of ESA and the International Congress of Entomology (ICE), defeating the University of Georgia. (See championship round on YouTube)
• 2015: UC won the national championship at the games held in Minneapolis, Minn., defeating the University of Florida. (See championship round on YouTube)

All branches of ESA conduct a Linnaean Games competition, with each branch sending the winner and the second-place winner to the nationals. The UC team has won the Pacific Branch (PBESA) competition multiple times. PBESA encompasses 11 Western U.S. states, plus several U.S. territories and parts of Canada and Mexico.

Some of the previous questions asked of the UC team during the championship rounds:

Question: What is the smallest insect that is not a parasite or parasitoid?
Answer: Beetles in the family Ptiliidae.

Question:Some species of mosquitoes lay eggs that can undergo diapause or aestivation. Give at least three cues that trigger the aquatic eggs to hatch. 
Answer: Temperature, immersion in water, concentration of ions or dissolved solutes.

Question: Chikungunya is an emerging vector-borne disease in the Americas. Chikungunya is derived from the African Language Makonde. What means Chikungunya in Makonde?
Answer: Bending up. 

Question: A Gilson's gland can be found in what insect order?
Answer: Trichoptera

Question: Certain Chrysomelid larvae carry their feces as a defensive shield. To what subfamily do these beetles belong?
Answer: Cassidinae.

Question: The first lepidopteran sex pheromone identified was bombykol. What was the first dipteran sex pheromone identified? Give the trade or chemical name.
Answer: Muscalure, Z-9-Tricosene. It is also one of the chemicals released by bees during the waggle dance.

Question: What famous recessive gene was the first sex-linked mutation demonstrated in Drosophila by T.H. Morgan?
Answer: White

Question: Cecidomyiidae are known as the gall flies. What is unique about the species Mayetiola destructor, and what is its common name?
Answer: Mayetiola destructor is the Hessian Fly, a tremendous pest of wheat. It does not form galls.

Question: Nicrophorus americanus is listed under what legislative act?
Answer: The Endangered Species Act

 Question: In what insect order would you find hemelytra?
Answer: The order Hemiptera.

Question: A 2006 Science article by Glenner et al. on the origin of insects summarized evidence that Hexapods are nothing more than land-dwelling crustaceans, which is to say that the former group Crustacea is paraphyletic with respect to the Hexapoda. What hierarchical name has been used to refer to this clade?
Answer: Pancrustacea

Question: What are the three primary conditions that define eusociality?
Answer: Cooperative brood care, overlapping generations, and reproductive division of labor

Founded in 1889, ESA is the world's largest organization serving the professional and scientific needs of entomologists and individuals in related disciplines. It is comprised of more than 7000 members, who are affiliated with educational institutions, health agencies, private industry, and government. Members are researchers, teachers, extension service personnel, administrators, marketing representatives, research technicians, consultants, students, pest management professionals, and hobbyists.

Resources:
Origin of Linnaean Games (Richard Levine in American Entomologist)
Previous Winners (Entomological Society of America)