Just figured it out... He's probably got worms! He's gotten skinnier since the spring when he first starting ta show up. Thinkin' finely chopped garlic mixed into can/dry food.
Anybody else wanna opine? (He's NOT gonna be easy to force into a box for a trip to a vet's ta check up). There's a PAWS 'small' animal hospital near here. Might ask...
He's obviously feral, with no means of support, and no home. Plus he does have fleas!
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Hmm. That address doesnt look right. It looks like the link pointing here was faulty.