I wonder if firefly broods are on multi-year cycles like cicadas. Like others in this thread have said, I've seen huge firefly, erh, "blooms", 25 and 15 years a

I wonder if firefly broods are on multi-year cycles like cicadas. Like others in this thread have said, I've seen huge firefly, erh, "blooms", 25 and 15 years ago. After the first one, and then subsequent years of not seeing such huge numbers, I thought I'd never see another one again. Unfortunately, I didn't have any chance to be out in some random field in Pennsylvania 5 years ago. They're definitely overall decreasing in numbers, though. 25 years ago was particularly big, but we still had fireflies every year after that. The last few years, I've found it pretty rare to see a firefly at all.