Skip to main content
Entomology 2025 Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.
 
Oral Presentation
Oral Presentation
Poster Display
Poster Display
Student Competition
Student Competition
Ticketed Event
Ticketed Event

Section Symposium

Plant-Insect Ecosystems

Innovations in Invasive Species Response

Oviposition, behavior, and establishment studies of Leucotaraxis silver flies: Insights into a specialist biocontrol agent of hemlock woolly adelgid

Wednesday, November 12, 2025
9:52 AM - 10:09 AM Pacific
Location: Oregon Convention Center, D137-138, OCC
Oral Presentation

    Presenting Author(s)

  • Olivia Andrews

    Graduate Student
    Virginia Polytechnic Institute and State University
    Blacksburg, Virginia

    • Co-Author(s)

  • CY

    Chin-Cheng Scotty Yang

    Assistant Professor
    Virginia Polytechnic Institute and State University
    Blacksburg, Virginia

  • AM

    Albert Mayfield

    USDA-FS Southern Research Station
    Asheville, North Carolina

  • MW

    Mark Whitmore

    Cornell University
    Ithaca, New York

  • TK

    Thomas Kuhar

    Professor
    Virginia Polytechnic Institute and State University
    Blacksburg, Virginia

  • SS

    Scott S. Salom

    Professor
    Virginia Tech
    Blacksburg, Virginia

After 20 years of release and establishment of two Laricobius spp. (Coleoptera: Derodontidae) predators throughout the eastern USA, additional predators are being released to help bracket predation throughout the target pest’s lifecycle. Other specialized predators of HWA on western hemlock, Tsuga heterophylla (Raf.) Sarg., in the Pacific Northwest, are two silver fly species, Leucotaraxis argenticollis and Le. piniperda (Diptera: Chamaemyiidae). To better understand their potential for biological control of HWA-infested eastern hemlock, Tsuga canadensis (L.) Carrière, we conducted laboratory and field studies to further understand the biology of these predators. The functional and numerical responses of both predators were assessed in response to different HWA densities. Le. argenticollis was able to significantly increase their oviposition and feeding with an increase in prey density, while Le. piniperda did not. Behavioral studies were performed using GoPros to record and differentiate potential oviposition/general behaviors in response to HWA presence on infested branchlets. Both males and females of both silver fly species were utilized for this study and assessed. Analysis of video footage is ongoing, and results will be presented. Simultaneously, release methods and timing for these predators were assessed in the field via caged and open releases in spring of 2022 and 2023. Monitoring for establishment was conducted from 2023-2025. Through 2024, no recoveries were confirmed from these releases. Updates will be presented on recoveries from the spring and summer of 2025 sampling.