Consider this-
My pond is only 1/5 an acre. I have seen ospreys, kingfishers and mergansers there. All these birds eat fish. Could a predatory bird transport fish from one pond to another ? A bird might need to bring fish home to hatchlings for instance. Or perhaps a bird of prey might bring a fish to a female bird as part of a mating ritual.
It's not any more far-fetched than the Turtle Theory.
