chatlanha, all the points you've brought up are all super-valid.
There've been a few threads where we've discussed various signs and the message intended to be delivered. Some were even as bold as "Shoot first, ask questions later." A lot of them were tongue in cheek.
I thought your approach was unique in that you were conveying a lot of information about the pond, and details about the inhabitants. If I recall correctly, I don't think anyone had tried that appoach.
How many people live in your neighborhood and have rights to the water?