Synchronized Fireflies at Congaree

Fireflies at Congaree National Park along the Bluff Trail.
Fireflies along the Bluff Trail May 2016 (Photo used with permission; Frederick Austin)
Synchronized Fireflies (May-June 2017)

FINAL UPDATE FOR 2017 (5/28/2017): Park staff have reported that the fireflies are no longer synchronized, as of the evening of Saturday, May 27. Although fireflies will likely be present in the park for several more weeks, it is highly unlikely that they will be synchronized.

The park would like to thank the thousands of visitors who came out over the past couple of weeks who followed our "Viewing Etiquette." The park would also like to thank the many dedicated volunteers and community partners who assisted during this time.

Today (Sunday, May 28) will be the final day of extended hours at the Harry Hampton Visitor Center (9am-9pm). The Visitor Center will resume normal operating hours tomorrow, Monday, May 29 (9am-5pm).

We look forward to seeing you (and the fireflies!) in 2018!

Viewing Etiquette & Important Info
  • Please be considerate to other visitors viewing this phenomenon.
  • Because of the increased number of visitors, we ask that everyone keep noise levels to a minimum so that everyone can enjoy this special natural occurrence.
  • Use red filters on your flashlights. Bright lights can disturb the fireflies’ flash pattern and make it difficult for other people to see.
  • Do not use flash photography. The flashing can be difficult to capture on camera/video.
  • Parking is limited. Carpool when possible.
  • Be prepared for the weather.
  • Fireflies are only here for a few short weeks. Please do not capture them in jars or take them with you.
Many children remember catching fireflies in jars when they were young, but not all fireflies are the same. With over 2,000 species found world-wide, there are only three species of synchronous flashing fireflies that can be found in North America. Every year, Congaree National Park hosts synchronous fireflies (Photuris frontalis) for approximately two weeks between mid-May and mid-June. During this time visitors can experience an awe-inspiring display of synchronous flashing while the fireflies search for a mate.
The best time to view the fireflies is just after dark, usually between 9:00pm and 10:00pm. The best viewing is along the bluff. The boardwalk is a popular place to view them and they can also be seen along Bluff Trail and in Bluff Campground.
The Harry Hampton Visitor Center will be open extended hours from Saturday, May 20 to Sunday, May, 28 2017. During that time, the Visitor Center will be open till 9:00pm each night and park staff and volunteers will be offering special programs.

Please note that the exact dates that the fireflies will "synchronize" each year is not known. This phenomenon could occur earlier in May or later in June. Factors including soil conditions and temperature affect when this natural phenomenon occurs.

This is the final update for the 2017 season (Updated on May 28, 2017)

Last updated: May 28, 2017

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Mailing Address:

100 National Park Road
Hopkins, SC 29061


(803) 776-4396

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