I took a long walk the other night. It was twilight, that magical time when the summer sky darkens to deepest blue -- and the mosquitos start to zing.

At a wooded area near the path leading into a wetland, I saw a tiny pulse of light. It was a firefly! I stopped to peer into the woods and saw another. Then another. They twinkled against the trees, putting on an enchanted lightshow that kept me so transfixed that I just stood there, watching, oblivious to the mosquitos feasting on my flesh.

I've always loved fireflies. Who doesn't? I can still remember moments from childhood, playing night games in the neighborhood, as fireflies winked in dusky back yards and the moms started calling us indoors for the night.

Then we moved to southern California, when I was 8. There were no fireflies but there was Disneyland. Next to the "Pirates of the Caribbean" ride there was a restaurant, the Blue Bayou, that evoked a Louisiana swamp at twilight. Thanks to Disney magic, its atmosphere included the sound of crickets and the flicker of fake fireflies. I always begged for our family to eat there when we visited the Magic Kingdom.

I don't see a lot of fireflies in my neck of suburbia these days. Stumbling across that cluster of them the other night made me wonder why I don't see them more often. Apparently I'm not the only one. Fireflies appear to be declining.

Some think herbicides, pesticides and fertilizers might be killing the lightning bugs. There's also speculation that development and the proliferation of artificial light is shrinking habitat and interfering with mating. Fireflies find their mates by flashing, and they must be able to see the flash and return it.

MCT - MCT, Star Tribune

Scientists are concerned to the point that they're asking a network of back-yard volunteers to track the bugs' range and numbers. Firefly Watch, a project of the Boston Museum of Science, debuted in 2008. If you want to post your own observations, visit www.mos.org/fireflywatch

Have you seen any fireflies this summer? Where did you spot them? And are you seeing them less often than you used to?