Yesterday evening, walking home from the train station, I saw a most wondrous sight: bats flying out in the dusk. At first I thought they were birds, but then saw the membranous wings, the blunt heads, the outstretched legs in place of feathered tails. They were departing from some distant roost, and they streamed overhead non-stop in loose groups, all flying in the same general direction. There was nothing inherently sinister about that flock of bats.
I marvelled at how silent they were. They made no sound apart from the faintest flap flap of soft wings. And, but it might have been my imagination, the faintest of chirpings. On and on they came; I must have stood there with my head craned upwards for a full five minutes, entranced by the bats.
Then I recalled, in a vivid flashback, an almost identical vision I had some years ago, watching a flock of corvids streaming overhead at sunset. Black crows in an endless stream, flying towards their night roost, cawing like commuters shouting news and gossip to each other as they made their way home. Now I saw the same vision, but these were bats, departing to forage and socialize, and possibly calling the same kinds of greetings to each other in their ultrasonic voices.
A fascinating mirror: one flock going home in the evening from their day activities, whilst another flock emerges at about the same time to go about the same business night. How wonderful!