Peak firefly season in Wisconsin runs from mid-June through late July, but many species can be seen from May through the end of August.

Lights Out Wisconsin is urging everyone to turn off or dim non-essential outdoor lights and close window shades from sunset to sunrise to help fireflies communicate and reproduce.

Another massive wave of migrating birds is on its way to Wisconsin, bringing calls from scientists to turn off non-essential outdoor lights on the night of May 14 and other nights over the next two weeks when Lights Out Alerts are forecast in some or all of the state.

Photo by Andy Reago & Chrissy McClarren

Extremely high bird migration is expected over Wisconsin tonight, May 11, and scientists from the Cornell Lab of Ornithology and Purdue University forecast a Lights Out Alert statewide.

People are urged to turn off non-essential outdoor lights from 11 p.m. to 6 a.m. tonight, and ideally, throughout the bird migration season ending in mid-June.  

Photo by Kelly Colgan Azar

For the first time this spring, Wisconsin communities have been added to the list of places receiving specific bird migration forecasts and Lights Out alerts from the scientists at Cornell Lab of Ornithology and Purdue University.

Photo by Kelly Colgan Azar

The Lights Out Wisconsin coalition joins in the celebration of International Dark Sky Week (April 13-20, 2026). This global celebration of the wonder and importance of the night raises awareness about the harmful effects of light pollution. It also calls attention to the darkness needed to sustain critical wildlife ecosystems. 

Photo by Joel Tonyan FCC

White-hot levels of bird migration are forecast for Wisconsin on Wednesday night, Sept. 24, spurring Wisconsin bird conservation groups and Dark Skies International chapters to urge residents, businesses and municipal officials to turn off nonessential outdoor lights from 11 p.m. to 6 a.m. on that night to save birds.

Graphic courtesy of AeroEcoLab