On a fine June evening, my pre-teen son and I ventured out at sunset to watch the sun go down over Lake Mendota. We found a grassy hill-top view from the iconic Observatory Hill on UW-Madison’s campus and awaited the golden hour. If you regularly track Wisconsin phenology, you might know what happened next. Slowly and quietly the field below us filled with a glittering array of duty-bound fireflies.

My son, who moments before was too cool to be seen sitting with his mother, threw off his headphones and bounded down the hill. The call of the firefly is too strong for even moody twelve-year-old boys to deny. The insects’ slow and floating manner and bewitching glow invites us in – to get a closer look, to have a fleeting face-to-face encounter with wildlife, to wonder at the phenomena of the natural world.

Neither flies nor bugs, lightning “bugs” are beetles with a semi-soft outer shell. While their light display is beguiling to humans, it’s actually designed to signal and attract a mate. The males flash in the fields while the females signal back from a perch in the surrounding shrubs or ground cover. There are about a dozen known firefly species in Wisconsin, each with their own unique flash- and flight-pattern. Their “glow worm” larvae are desirable in backyard gardens given their appetite for slugs, snails, and cutworms.

Lightning bugs’ bioluminescence is created by the enzyme luciferase which reacts with the organic compound luciferin and oxygen to emit light. This is a very efficient way to generate light as 90 percent of the energy transfer is used to produce light, not heat. An incandescent light bulb, conversely, uses 90 percent of the energy transfer to produce heat – only 10 percent creates light. Not surprisingly, scientists are attempting to harness this unique light production in medical processes, including tagging cancerous tumor growth, and tracking COVID antibody reactions.

Find out more about these captivating insects from:

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News from Nature Net Members

The Madison Children’s Museum is now open for members and will open to the public on June 24th. Ticketed entry times begin at 9am from Thursday to Sunday. Make sure you book your tickets before they fill up! Dane County Parks has a new park! The 140-acre  Joyce M. Baer & George J. Socha Conservancy is east of Sun Prairie, just 30 minutes from downtown Madison. Hike, explore and visit glacial drumlins. Lussier Family Heritage Center’s Movies in The Park have started back up! Bring your lawn chair and some spending cash for refreshments from Karben4 and the Chocolate Shoppe. Catch the next movie on July 1st.


More from Nature Net…

For Families: For Educators: Upcoming Events:
Complete summertime nature missions online with the new Nature Passport! Unique challenge that are fun and easy for the whole family to do! Educator training opportunities abound throughout the summer. Check out the Nature Net Calendar of Events for upcoming workshops and classes. The summer calendar is bursting with fun family events. Check back frequently for updates and inspiration for outdoor activities.

Funding for Nature Net and the Nature Net News blog is provided by American Girl Fund for Children.
Content Creators:
Betsy Parker, Nature Net Director
Karissa Niederkorn, Nature Net Intern