Re: How to do a TNR when you find a cat in the middle of nowhere
The only way is to bait a humane trap with some good-smelling cat food. In such a public place, I would stay nearby and keep an eye on the cat and trap to prevent anyone messing with it and/or taking or springing your trap. I think you would have the best luck if you only set and place your trap when you see the cat.
Check wind-direction and place the trap and food up-wind so the breeze will carry the enticing smell to the kitty. Then hope the kitty follows its' nose and its' stomach overrides it's fear of entering the trap.
Our WalMart had some cats living in/around the outdoor garden area and I asked about them when I saw them slinking around one night. Some employees had already TNR'd them, one built a winter shelter for them and they were fed/watered daily.