It could be a tree frog also, I heard a noise after dark when I let my dog out, tree frogs chirp and crickets it's almost like singing sound.For at least two weeks almost every night when I go to bed about 11;30, I hear a faint chirp-like noise. When I open the window at 9:30, there‘s nothing. It’s a similar sound and rhythm to a smoke alarm battery that’s wearing out. It seems like it’s in the distance. It’s also like the warning sound of heavy equipment backing up. I can’t think of any bird or animal that makes this sound for a few hours. Tomorrow I’ll report if I heard it again.
I had to listen for a minute before it clicked that it was tree frogs, It's been cold the last couple night so not heard it. They will be back out
when the nights warm up again. Look on You Tube for sound bites of each, see if that is what is was.