More than 10 percent of American fireflies nearing extinction

About 11 percent of the North American firefly species assessed in a recent study are threatened with extinction

Researchers from the Xerces Society, the ABQ BioPark and the Firefly Specialist Group of the International Union for Conservation of Nature evaluated 128 firefly species and found that 14 are threatened with extinction.

Another 2 percent – 3 species – are “near threatened, while 33 percent are of “least concern” and “too little is known” about more than half of them “to assess whether they are secure or at risk.”

There are at least 167 species of firefly in the U.S. and Canada, but the researchers could find monitoring data on only 128 of them.

Of the 14 species that are threatened with extinction, the most threatened is the Bethany Beach firefly, which was categorized as critically endangered.

The species was petitioned for emergency Endangered Species Act (ESA) listing by the Center for Biological Diversity and the Xerces Society in 2019. It received a positive 90-day finding and will undergo a full status assessment by the U.S. Fish and Wildlife Service.

Another 7 were categorized as endangered, 6 as vulnerable and 2 as near threatened. Many of them have narrow geographic ranges, specific habitat requirements, and life history traits such as flightless females or bioluminescent courtship behaviors that make them more vulnerable to extinction.

Although the threats for each species vary, the main drivers of decline appear to be habitat loss and degradation, light pollution, and drought and sea level rise associated with climate change.

“These assessments — the first for fireflies — lay the groundwork for firefly conservation in the U.S. and Canada,” said Candace Fallon, a senior conservation biologist at the Xerces Society.

“With this information, we can now be more strategic about setting conservation priorities and addressing data gaps, working to protect the full diversity of fireflies and their habitats, from the common and widespread big dipper firefly to the threatened and little-known southwest spring firefly.”

The assessments highlight the need for species-specific conservation actions coupled with monitoring efforts to document long-term population trends for threatened species.

Additional research is also needed to properly assess the large number of species currently categorized as “data deficient.”

But the researchers found it encouraging that many of the species assessed are still thriving, and that the conservation actions needed to maintain populations and protect at-risk species are not limited to government entities or conservation organizations.

“The good news is that everyone can play a role in bolstering firefly populations,” said Anna Walker, BioPark Society species survival officer.

“We can turn off lights at night to reduce our individual contributions to light pollution, we can participate in community science projects like Firefly Watch that gather data on firefly distribution and abundance, and we can support organizations that protect and restore the habitats that fireflies need.”