Why Are Moths Attracted To Light?

Jun 23, 2017

In this episode we're celebrating the official return of summer to the northern hemisphere by answering some summertime questions! How do fireflies glow and can they control how they blink? Why are owls nocturnal? How do they swivel their heads around? And how do they hoot? Plus a few burning questions about why bug bites itch, why poison ivy and caterpillars and berries can all be poisonous, and how come we have to wear sunscreen!

We'll get answers from wildlife biologists Kent McFarland and Bryan Pfeiffer. Plus we hear an episode of one of VPR's other podcasts, Outdoor Radio.


Listen to the full episode for all of the answers.

If you're interested in fireflies, you can take part in a citizen science project at the Museum of Science in Boston. The museum keeps track of people's observations of fireflies through its Firefly Watch project. That's also a good place to go to learn more about fireflies and how you can help preserve them.

And if you want to do some backyard moth observations, you'll need a few supplies. Outdoor Radio hosts Kent McFarland and Sara Zahendra recommend hanging a white sheet up and shining a black light or a mercury vapor light, available at pet stores, onto the sheet. Watch and see what kinds of moths are attracted to the different lights.

You can also try smearing a sweet sticky concoction onto the trunk of a tree to attract moths that don't respond to light. Maple syrup, honey, mushed up bananas, even beer all work. Then shine a flashlight onto the trunk after dusk to see what kind of animals are having a snack.

It's pretty easy to photograph the moths and other animals while you're shining lights on them. And if you need help identifying what you've found, try sending your photos to the online Bug Guide or looking in one of the many field guides to moths and insects.

If you wind up taking photographs of moths, or trying your hand at mimicking a firefly, let us know how it goes! Send your photos and stories to questions@butwhykids.org.

That's also where you can send any kid questions you want our podcast to answer. Stay curious!

Read the full transcript.

Heidi, 6, far left, lives in Kansas. Matthew, 7, lives in Annapolis, MD. Jora, 10, lives in Hinesburg, Vt. Izzy, far right, 5, lives in Minnesota.
Credit courtesy from parents

Pippa, far left, 6, lives in West Linn, Oregon. Vonn, 6, lives in Parkville, MD. Samarah, 8, lives in Johnson, Vt. Rowan, 4, far right, lives in Juneau, Alaska.
Credit courtesy from parents

Thatcher, left, 4, lives in Easton, New Hampshire. Melbourne, 6, lives in England. Sophie, right, 10, lives in Washington, DC.
Credit courtesy from parents