OK, this isn't exactly David Attenborough footage... but I'm very fond of this white heron. We bought our apartment on the edge of Ross Creek (and yes, still in the heart o' the city) in the winter of 2000. That winter and every winter since, this lone white heron has come to fish in the shallows at the half-tide.
I'm sure it's the same bird. It comes at the same time every year, always alone. I love to see him (her?), and I have no idea where he is for the rest of the year, but it's another of the wonderful cyclical mysteries of Nature, isn't it? Do you have any recurring visitors where you live?