Thanks for the barrel idea. I have had to release trapped rats from trash cans, so your idea has precedent...
The last name thing gets weirder.. my late husbands first name was Paul.
Others have also cautioned that snakes take the sun on the hard scapes during the day- and will frighten the guests. There is also a low profile fountain feature that may also attract snakes to swim. A potential for syncronized snake ballet. I want to learn more about black garden snakes, and calculate the installation. Perhaps after all the benefits and risks are weighed, the best tact may be to hide them in plain sight. A feature story in the paper about the benefits..." come and view the rat attack army on the plaza."
How quickly will 10 grow to a hundred... how long till they grow enormous on the rat population? If you know of any black garden snake resources... please forward.