He went home today. We got a call this morning and found out he lives a few streets over. It's a good thing I put out the big neon posterboard signs yesterday. There's no way his people would have seen the other signs I had up. We learned his name is "Agate", like the stone. He belongs to a lady in her 80's and it was her neighbor who called. He usually takes Agate and his brother for walks on Sundays since their owner has hip problems.
So he in now in his own yard with his brother who I'm sure is very happy to see him. Apparently he got out of his yard on Tuesday. No wonder he was so hungry and thirsty when we found him on Wednesday!