The mother cat, A.K.A FP 124 and her juveniles, FP 125 & FP 126 were within a few yards when we were backing the research boat into its parking place. Take it from me, they also make a chirping sound much like a bird.
Since birds usually don't make sounds at night, the chirping is usually a couguar.
What kind of animal (upper midwest, nightime) makes a sound like a police siren? I mean so much like a police siren that the first time I heard them moving up from across the field, I thought I was hearing a bunch of emergency vehicles off in the distance. It was uncanny.
Since that first incident a few years ago, I hear them off and on at night. Sets my dog off like mad, drive him crazy (Rottie, is inside). He will bark like I've never heard him bark at anything -- and, they can apparently hear him, from inside the house (him) and across the rield (them), so they must have fairly good hearing, whatever they are. When he starts barking, they stop "sirening".
A relative who grew up here had never heard anything like it before, it scared the crap out of him. Most people I describe this to, will give a knowing nod of the head, and say something like, "Coyotes, yup, coyotes, no doubt about it", but, they don't sound like any coyotes that I've ever heard -- nor did they sound like coyotes to my relative who spent his life growing up in this rural area.
waaay late for a reply but that chirping is the bird in the belly of the cougar. "The cat that ate the canary"