Invasive fruit flies attack more than 300 of California's crops, ranging from fruits and nuts to berries and vegetables, causing millions worth of dollars in damage annually.

That's why it's important to learn how to identify these pests, such as what occurred at a three-day training workshop held recently at the California Department of Food and Agriculture's Plant Pest Diagnostics Laboratory. 

A USDA Farm Bill grant funded two workshops. Grant recipient Luc Leblanc, curator and manager of the William F. Barr Entomological Museum, University of Idaho, Moscow, organized and led two three-day workshops, free to registrants. The first took place Feb. 24-26 in Gainsesville, and the second, March 11-13 in Sacramento.

CDFA senior insect biosystematist Martin Hauser, who assisted with the training, said it well: "There are just not many people worldwide who can identify these important pests. They cause millions and millions of dollars in damage every year. And like in human diseases, it is crucial to have the correct diagnosis, otherwise, it is impossible to implement the correct counter measures and fix the problem."

Sadly, however, due to the loss of federal travel funds, some of the USDA scientists registered to attend could not. Some  attended remotely.

The main focus: the subfamily Dacinae (Asian and African genera: Bactrocera, Ceratitis, Zeugodacus), the South American Anastrepha and the genus Rhagoletis (mainly Europe and North America).  

Leblanc provided "every one of the 10 in-person participants (California, Puerto Rico) with a set of 16 different pest fruit flies (which he collected himself in Bangladesh, New Caledonia, and the South Pacific), an insect collection box, pins, and other equipment," Hauser said. “Everybody learned how to pin, and curate their own collection. The participants could keep the flies and insect boxes. Later everybody learned how to identify their specimens with a manuscript key of pest fruit flies, written by Leblanc.” 

A slide from Severyn Korneyev's presentation. He is a CDFA environmental scientist and a Bohart Museum associate.

Some of the world's most prominent Tephritidae experts delivered lectures.

Leblanc and Severyn Korneyev, an environmental scientist at CDFA and a research associate at the Bohart Museum of Entomology, UC Davis, gave in-person presentations. Leblanc's topics: “Dacini Classification and Morphological Characters”; "Management of Fruit flies in the Pacific Islands”; “Identification and Ranking of Pest Species of Dacini”; and “Fruit Fly Surveys in Asia and Oceania.” Korneyev shared “An  Overview of the Pest Species of Rhagoletis"
Three others delivered online presentations via zoom: 

• Jung Wook "Woogie" Kim of the USDA-APHIS (Animal and Plant Health Inspection Service) presented  “An Introduction to Tephritidae Morphology and Classification”
•  Erick Rodriguez, research scientist and curator of Diptera, Division of Plant Industry, Florida Department of Agriculture and Consumer Services,  “An Overview of the Pest Species of Anastrepha” and “Introduction to Characters and Identification of Tephritid Larvae.” 
• Karamankodu Jacob David, National Bureau of Agricultural Insect Resources, Bangalore, India,  "Diversity of Dacini in India with Special Reference to Economically important Species.”

Talks Online. The talks will be posted online through the Dipterists Society, https://dipterists.org/. 

The response from all participants, in-person and online, was "very positive." Plans call for similar workshops.

Two UC Davis-affiliated scientists participated in the Sacramento workshop: UC Davis doctoral student Carla-Cristina "CC" Edwards of the lab of medical entomologist-geneticist Geoffrey Attardo of the UC Davis Department of Entomology and Nematology; and Brennen Dyer, collections manager, Bohart Museum of Entomology.

CC Edwards. “I found the workshop very helpful!” said Edwards.  “We learned how to identify various fruit flies, as well as a technique of double mounting. The workshop was great as we were provided specimens to ID, but we also got to keep them as a guide for the future. As someone focused on mosquitoes and insecticide resistance, I see parallels between the challenges of mosquito and fruit fly management. Both require accurate species identification, resistance and strategic control measures to mitigate their impact. Workshops like this help bridge gaps between disciplines, improving our ability to detect and respond to pest threats.” 

Brennen Dyer. "It was a fantastic workshop," Dyer said. "Being hands-on from vial to determination label is the best way to learn a group, in my opinion. But walking away with a reference collection is the best part, and now if any of these flies come through the Bohart Museum, I will be in a better position to correctly identify them. The talks from Luc and other experts did a great job rounding out both the theory and practice of fruit fly biodiversity and control efforts across their native and adventive ranges.”

CDFA's Target Pest Profiles, posted on its website, include the Guava fruit fly, Malaysian fruit fly, Mediterranean fruit fly, melon fruit fly, Mexican fruit fly, Oriental fruit fly, peach fruit fly, Queensland fruit fly, Tau fly, and the white-striped fruit fly.

Caption. The class gathered for a photo (see image below). Kneeling are Severyn Korneyev (left) environmental scientist, CDFA Sacramento, and Abraham Lopez Zuniga, agricultural technician 1, CDFA, Los Alamitos. In back (from left) are Luc Lebanc, curator of the William F. Barr Entomological Museum, University of Idaho;  Umesh Kodira, EPM-II, CDFA, Sacramento; Martin Hauser, senior environmental scientist (supervisory), CDFA, Sacramento; Carla-Cristina “CC” Edwards, doctoral student, UC Davis; Kevin Nguyen, environmental scientist, CDFA, Los Alamitos; Nisael Nieves, entomologist, USDA-APHIS,  Puerto Rico; Mitchell Gleason, pest prevention assistant, CDFA, Los Alamitos; Nolan Casey, pest prevention assistant II, CDFA, Los Alamitos; Brennen Dyer, Bohart Museum of Entomology, UC Davis; and Alex Mendenhall, Tulare County Agricultural Commissioner office, Tulare.