Swallow-wort Biocontrol

Cage Monitoring in SLELO PRISM

Native to Ukraine, swallowwort was likely introduced to North America as an ornamental plant, soon spreading to several northeastern states. The plant creates extremely dense monocultures spreading over acres upon acres of otherwise biologically diverse natural systems. The biological control, Hypena opulenta, is also from the Ukraine and feeds exclusively on swallowwort.

Partnering with the NYS Invasive Species Research Institute, the Thousand Islands Land Trust, SUNY ESF, University of Rhode Island, the USDA Agricultural Research Service and local volunteers, our SLELO PRISM assisted with caged releases of Hypena opulenta at four sites within the Eastern Lake Ontario and St. Lawrence Region. This important work will help to restore Priority Conservation Areas (PCA’s) to their natural ecological

Identifying hypena opulenta

Hypena opulenta adults are one cm long with a wingspan of about 3cm. They have dull, light brown forewings with a dark band in the middle and hindwings that are pale orange. 

The larvae start out white, but later become green with black spots and a yellow head. 

The life cycle of Hypena starts with the emergence from the egg as a larva.  This larva goes through five stages or instars. The last molt occurs at the end of the 5th instar and transforms the larva into a pupa.  Metamorphosis occurs inside the pupa and results in the emergence of an adult winged moth. 

Adult Hypena opulenta lay between 400 to 600 eggs during an average 2-3 week lifespan.  Two generations may occur in the same year. The larvae feed exclusively on pale and black swallowwort and this was the reason that they were selected as a biocontrol.

2021 Cage Monitoring Overview

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2020 Cage monitoring overview

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Photos from the field

NYISRI has brought together researchers from various universities to create the Swalow-wort Biocontrol Research Collaborative.

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Webinar Recording

Hosted by the Eastern Lake Ontario Swallow-wort Collaborative on March 23rd, 2022. This webinar showcased swallow-wort biocontrol research that is currently underway in New York state and beyond. Researchers from New York, Rhode Island, and Michigan provided an overview of their research, along with the results of an ongoing Hypena opulenta cage monitoring project that SLELO PRISM participates in. PRESENTED BY:

  • Dr. Lisa Tewksbury- University of Rhode Island Biocontrol Lab
  • Dr. Marianna Szucs- Michigan State University
  • Robert Smith-SLELO PRISM
  • Dr. Dylan Parry- SUNY ESF

Visit the ELOSC Webinar Recording Library