The synchronous fireflies are at it again in the woods and even in the yard near the house. I've been watching them at the farm here and at our previous house for at least 25 years now. The first few nights I see them there are not many and they are not quite synchronized but in just a few days they are everywhere and synchronized nicely. They stay fairly low at first, about shoulder height or lower, but later tend to move higher in the trees. Their flash is a series of very short blinks unlike normal fireflies whose blink is slow enough to see a trail when they move.
It's fascinating to see 50 fireflies all blinking in perfect unison. Every once in a while a rogue flies in from another area out of sync but he quickly gets with the local program.
It's humorous to hear of people paying for a lottery ticket, paying driving hours, paying a big parking fee, then waiting for their turn to be shuttled to a viewing area in the Great Smoky Mountains. When I was working a woman told of her viewing adventure in the Smokys then got visibly upset when I told her I watch them in our woods every year. Not too many years ago insect scientists declared they were only found in first one, then two areas in the country. I wrote to some researchers and told them about ours but never heard back.
Once I collected a bunch with a net and put them in our screen-in porch. They didn't blink once!
JKJ