You should call The Cat House first! They have a Trap-Neuter-Return program, and it sounds like this cat is part of this. If this is the case, they have volunteers keeping an eye on them.
You would probably have to take the cat to the cat house and they will have it checked out. They will scan the cat for a microchip and see if the owners have lost there beloved pet. If not they will have the cat checked out a probably put up for adoption.
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