Helicopter pilot reported a NMAC event in SFAR airspace with another helicopter that was not communicating on frequency. Evasive action was required to avoid a collision.

Narrative

At night; I was flying a Part 91 tour of ZZZ and reported my position; route of flight and descending altitude on the CTAF as I crossed the Bridge heading southbound stating that I was going around the Landmark 1 and straight to Landmark 2. I heard another helicopter report that he was leaving Landmark 2 and heading northeast in my direction. I saw the aircraft and descended further to avoid his flight path; when just north of [the] Island and out of no where; another helicopter passed by me within just a few ft. of separation! I never heard that aircraft report his position and seemed to turn on his lights just before potential impact. Post investigation on my part; I saw the culprit helicopter on an aircraft radar site and that he came from a northern direction and was making a large turn around the Landmark 3 to make a landing at ZZZ1 heliport. This whole incident could have been avoided had the pilot made his required radio position report and had his lights on. Adding further insult to injury; I was preoccupied with keeping my visual separation with the Landmark 2 helicopter; flying at and over me. I strongly believe that further prevention of these incidents could be made by not just keeping the already established ZZZ Exclusion and its position reporting rules; but also establishing MANDATORY routes for aircraft to fly while in the Exclusion when transgressing certain areas from different directions.