You're very likely right, Sam, but then what else do you do? Maybe the commercials could arrange something.
Edited bit : Yes, post a notice stating that one Sunday (or any popular day) the lake is closed for 'Training Purposes' and invite all those who wish to have a fish - FREE of charge providing they attend the training when it takes place during the day. Bit of incentive there...
I remember our Ian (FM's editor) arranging a pike fishing training day at Thorpe Park some years ago with John (forget his second name, bit like Synow - no?). Good day, I took down a young lad, but there were only two pike caught if I remember.