Update for Paul (and anybody else)

You ask after Mr Heron. I think he must be alive and well, but I haven't seen him for months. I certainly did not poison him, shoot him or otherwise do him any harm, but he has been conspicuously absent.

 However, as I hope you can see: his absence may have everything to do with the net which is stretched across the whole pond, plus the plastic netting fixed around the sides of the pond. He may have tried to land on this net without telling me, but I think he would get a bit of a bouncy shock, which would put him off from ever trying to do it again.
On the other hand, if you look closely at the second picture, of the fish tank, you will see that I have some concern for its future.

This tank, which holds about ten fish, is showing its age, or at least the supports are. I had the tank put in place long before the pond, and the wooden frame is rotting away. Even more of a problem is the 'table' supporting the filter tank (You may also see here the Heron Countermeasures which are in place). I have yet to decide what to do about it, but I hope I can decide before the whole thing collapses!