Bumps in the night, and screeches, and screams

I'm a light sleeper. I get completely zonked from about 11.00pm - 3.30am then I hear everything from the fridge kicking in with its distinctive rev and hot hissing sound, to dogs walking on the mulch looking for somewhere to pee, to DrummerBoy's drunken return from the RSL and feeble attempts to sneak out doona's and mattresses for other's too drunk to lift a finger. Then there's Frog Mouthed Owls who have a call reminiscent of those deep breather's that nuisance call occasionally but there's one noise in the night that I just can't identify. I can hear substantially sized animals in the pine and bamboo immediately outside my family room window. Not sure if they're fruit bats or possums and every attempt to expose the blighters is foiled by their rapid movement through the trees. They're noisy, the dogs go ape shit and by the time I've reached for the mag-light, they've travelled well up the fenceline and into the neighbour's arbour, their screeching diminishing as if to taunt me and say "catch me if you can biatch". I will find out what they are . . . .