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TV Crew Visits Oregon Research Cages


Last week, a television crew from KGW8 News traveled to Aurora, Oregon to film a growing research project focused on one tiny insect causing major concern for mason bees across North America.
Reporter Katherine Cook visited the experimental insect cages where researcher Abigail Lehner from UC Davis, and Thyra McKelvie, from Rent Mason Bees, are studying the invasive Houdini fly and its impact on mason bee populations.
The story, titled “Scientists study invasive ‘Houdini fly’ threatening mason bees in the Northwest,” highlighted how researchers are racing to better understand this rapidly spreading predator and develop solutions before infestations become even more widespread.
Inside the Research Cages
The Oregon project uses large outdoor insect cages where mason bees and Houdini flies are released together under controlled conditions. Researchers can closely observe:
- How Houdini flies locate mason bee nests
- When they enter nesting cavities
- Reproduction behavior
- How infestations spread
- Which bait traps may help reduce populations
The Houdini fly, originally from Europe, is considered a kleptoparasite. Instead of attacking mason bees directly, the fly sneaks into nesting chambers and lays eggs on the pollen provisions meant for developing baby bees. The larvae then consume the food source, causing mason bee larvae to starve.
One of the most alarming facts discussed during filming is the reproductive imbalance between the two insects. A mason bee may only lay around 15 eggs in her lifetime, while a single Houdini fly can lay hundreds.
Why This Research Matters
Mason bees are among the most effective spring pollinators in North America. They pollinate up to 95% of the blossoms they visit and are essential pollinators for backyard gardens, orchards and many fruit crops.
Researchers now believe the Houdini fly is established across large parts of North America, including the West Coast, East Coast and western Canada.
The KGW8 segment helped bring public awareness to a problem many gardeners have never heard of, despite seeing fewer mason bees emerging from backyard bee houses in recent years.
A Collaboration Between Scientists and Backyard Gardeners
One of the most important themes in the interview was citizen science.
Researchers rely heavily on backyard gardeners and mason bee hosts to report infestations, monitor nesting materials and help track the spread of the Houdini fly. Proper mason bee stewardship is becoming increasingly important.
The research team recommends:
- Using nesting materials that can be opened and inspected
- Avoiding bamboo and drilled blocks
- Removing nesting materials in early summer
- Harvesting and washing cocoons in the fall
- Monitoring for Houdini fly larvae and adults
The Washington State Department of Agriculture has also published management recommendations encouraging openable nesting systems and cocoon harvesting to reduce infestations.
Media Attention Helps Spread Awareness
The KGW8 story gave viewers a rare behind-the-scenes look at real pollinator research happening in the Pacific Northwest.
Television coverage like this plays a critical role in helping gardeners understand:
- Why healthy bee stewardship matters
- Why proper nesting materials are essential
- How invasive predators are impacting solitary bees
- What homeowners can do to help protect pollinators
The segment also highlighted the collaborative work between UC Davis, researchers across the country and Rent Mason Bees to better understand the Houdini fly and protect future generations of mason bees.
You can watch the full KGW8 story here:
Scientists study invasive ‘Houdini fly’ threatening mason bees in the Northwest



