We had rats — I wanted to catch them without harming them. Things were going well but it came down to one recalcitrant holdout who had learned all of my tricks, and I had to resort to some extreme measures to try to catch it. Music is from my album Frost Flowers: http://caseyconnor.org/?p=disco
All these rats were released unharmed — it’s nonetheless likely that they had a hard time being dropped into a new location without a nest or food stores. It seemed like a reasonable compromise. I left them a sort of care package when I released them, but I do have a feeling the local owls were happy to see me coming.
If you’re trying to decipher the notes in the schematic, the reference to the “arduino” and the “Pi” are referring to the case where the NPN/solenoid is being triggered by a logic signal from those devices, instead of a 555 timer. Sorry for the confusion there.