KEENE, N.H. (MyKeeneNow) Favorable conditions for amphibian migration are expected Tuesday night, but thunderstorms in the forecast are prompting officials to urge the public to stay home and avoid local crossing sites.

The City of Keene, working in partnership with the Harris Center for Conservation Education, plans to close portions of North Lincoln Street and restrict through-traffic on Jordan Road beginning around 7:30 p.m. Tuesday, April 14, through 7 a.m. Wednesday. The closures are designed to protect frogs and salamanders as they make their seasonal journey to breeding wetlands during what is commonly known as “Big Night.”

However, due to the risk of thunder and lightning, organizers are asking residents not to visit the crossings. Harris Center naturalists will also not be stationed at the sites if storms develop, citing safety concerns.

“Big Night” occurs on the first warm, rainy evenings of spring, when thousands of amphibians emerge and cross roadways to reach vernal pools. While the weather conditions may be ideal for migration, they can create dangerous conditions for people observing the phenomenon.

Keene has become a leader in amphibian conservation efforts, becoming the first community in New Hampshire to temporarily close roads for migration events. The North Lincoln Street closure, first implemented in 2018, was later expanded to include Jordan Road in 2022. The initiative is supported by data collected through the Harris Center’s Salamander Crossing Brigade, a volunteer-driven community science program.

Over nearly two decades, volunteers have helped tens of thousands of amphibians safely cross roads in the Monadnock Region, while also documenting significant road mortality. Officials say even low levels of traffic can have a major impact on amphibian populations, making road closures a critical conservation tool.

On nights without severe weather, the North Lincoln Street site is typically open to visitors, with families encouraged to observe the migration safely. Jordan Road, however, is limited to trained volunteers due to safety and access concerns.

Residents looking to experience a Big Night are encouraged to monitor future forecasts and visit on a safer evening. Updates on road closures and migration activity are available through the Harris Center’s salamander forecast page.