Where have all the butterflies gone?
If you’ve noticed fewer butterflies fluttering around your garden lately, you’re not alone. Many insect populations are in decline, and butterflies are no exception. According to Virginia Tech entomologists, they face a variety of challenges, such as habitat destruction, improper use or overuse of pesticides, and climate change. These factors also affect lightning bugs, dragonflies, and other groups of beloved and beneficial insects.
Virginia Tech entomologist Theresa Dellinger offered insight into why butterfly numbers may be dwindling and what we can do to help.
What’s threatening butterfly populations?
Habitat loss: “As fields, grasslands, and forests are cleared for development, butterflies lose the host plants their caterpillars need to survive. What may look like an empty field to us is actually a critical habitat for many insects.”
Improper pesticide use: “Many pesticides used in farming and home gardens don’t just target pests — they also harm butterflies and other beneficial insects. Broad-spectrum insecticides, including those used for plant pests and mosquito control, can be particularly harmful.”
Climate change: “Extreme weather events, including unseasonable heat, cold spells, droughts, and heavy rains, can disrupt butterfly life cycles. If caterpillars hatch when their host plants aren’t available, they struggle to survive.”
How can you help?
Create butterfly-friendly spaces: “Even small changes in your yard or garden can make a big difference. Consider planting host plants that butterflies and caterpillars rely on. Your local Master Gardener or Master Naturalist program can offer expert advice.”
Use pesticides wisely: “If you must use pesticides, follow the instructions carefully and apply them only when necessary. Master Gardeners and Master Naturalists can also recommend safer alternatives.”
About Dellinger
Theresa Dellinger is a diagnostician in the Insect Identification Lab at Virginia Tech, where she specializes in insect taxonomy and assists in training state personnel in insect identification and management practices.
Interview
To schedule an interview, please contact Margaret Ashburn at mkashburn@vt.edu or 540-529-0814.