My wife and I did another 1.7 miles this evening. The temperature had been 95 (F) during the afternoon, but when we went out, the temperature was down to 81. We went late in the evening, just minutes before the sun set below the Oquirrh mountains. We could still see the path when we finished, but about 15 minutes later, it was dark. I didn't carry water with me, but we had good drinks from the fountain at the parking lot before and after our workout.
There were a lot of birds and animals out during our run. I frequently see swarms of starlings flying to trees during dusk, but I didn't see any during my workouts Monday or this evening. I did see a lot of birds flying around, but they weren't in swarms. Actually, I couldn't tell if they were birds or bats. What ever they were, I hope they ate a lot of insects, because there are a lot of small gnats flying into my face -- no bites, just the bother of the gnats flying into my face.
The following picture of bats flying in the trees was taken from the web.