I’d appreciate assistance identifying the source of a sound we heard from high in the trees last weekend in SW Mich - NE of Muskegon.
The call was a single note, repeated maybe 10-15 times. The most significant aspect was that the frequency with which it repeated slowed - reminding me of a motor slowing down and stopping. I do not know how best to represent the sound. The closest I could vocalize was by clucking my tongue with my mouth open. tooktooktook took took. took. took. took
There was almost a guttural aspect to it, reminiscent of a swallowing noise.
It was high in the trees - white oaks. Near a lake. Temps in 80s. I think I heard it most in the midday. It would be repeated a few times (5?) but not over and over. Then I might hear it from a different tree- but not like a call/response. That made me suspect a bird (tho I never saw one obvious). My search of bird/frog sounds has been unsuccessful.
So what did I hear? A bird? Frog? Insect? Arboreal chupacabra?