WATCH: Are fireflies going extinct? Not exactly

Social media has been abuzz with fears that fireflies are going extinct — and that this generation may be the last to remember summer nights spent catching them.

The good news is that fireflies aren't totally disappearing, said biologist Candace Fallon, who leads the firefly conservation program at the Xerces Society. But out of the more than 175 firefly species across the U.S., 18 are what they call "threatened with extinction," which means they are likely to disappear in the near future.

"The real issue I think is that over half of the species in the U.S. are considered data deficient and that just means we don't have enough information to assign a category," Fallon said.

Why don't we know more about fireflies? Fallon said some fireflies are active in the daytime and may lack the signature glow. Another factor: Researchers only see fireflies for a fraction of their lives. Firefly larvae can live up to two years underground, followed by only a few weeks aboveground as adults.

"It makes it very difficult because we have a very short window for each species, and you have to be in exactly the right time at the right place in order to find them and count them and see how they're doing," Fallon said.

Habitat loss and degradation are the biggest threats to fireflies, followed by light pollution, pesticide use and the effects of climate change. Fallon says there are ways people can help protect fireflies in their own backyards: Leave some wild spaces in your yard. Limit use of pesticides, which kill fireflies and their larvae. Fireflies use their flashing light patterns to communicate and reproduce, so be mindful about the use of light at night — turn off outdoor lights that are not needed.

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