Bat Squeaks?

Last night I saw a bat flying above the parking lot of my apartment complex! The pink membranes of its wings were lit up by the orange glow of the street lamps. It flew in a chaotic pattern, like some small butterflies do.

That bat was cool. I followed its flight for as long as I could, and then it disappeared. How cool would it be one day to see a bat catch a moth in mid-air?

Then tonight, after a huge rainstorm, tons of toads starting bursting into song. But lately I’ve also been noticing this different sound amongst the usual toad choir. It’s a series of short pipsqueaks, in 2’s or 3’s, sometimes more, and sometimes irregularly paced. I’m hearing it right now. The sound doesn’t have the same feel as a toad’s, with that membraney, vibrating, drone quality. It sounds much more guttural, almost like a bird, or some tiny mammal squeaking. Plus it has none of that regularly paced character of a toad, like if the toad were just blowing air up and through his throat, as mechanical as flapping on a drum. I searched around on the net and I think the pipsqueaks that I’m hearing may be the chirps of a big brown bat. It sounds very similar to Sound #2 I found on this site:
http://www.fcps.edu/islandcreekes/ecology/big_brown_bat.htm

As I’m writing this, the toads are reaching an almost deafening crescendo, and the bat, if it is indeed a bat, is squeaking above it. Maybe I’m wrong and the noise I’m hearing is just some other species of frog or toad, a lonesome one calling to a chorus of turned ears. Perhaps now that the rain stopped, there are billions of mosquitoes about for this bat to eat. I would love to see where it roosts in the daytime. I wonder if it roosts by itself under a tree, or does it join hundreds of other bats somewhere? Bats are so mysterious!