Phizzy - "Overhead there regularly flies a Heron, visiting one or other of the adjacent lakes/ponds, he looks like a Pterodactyl to me."
Do they ever.
I remember those from when I lived in the Lower Mainland, BC...
...they look like pterodactyls 'cause their long legs sticking out behind them resemble a tail.
I'm embarassed to say I actually though that's what one was, one time.