My second-hand information from one Russian fella who spearfish in Turkey regularly. Your boat operator will need a license, you don't need and cannot have it as you are not resident in Turkey. Apparently he has got this information from the source, the office in Turkey that sells fishing licenses, SU ÜRÜNLER. What also was said to him while he was in Su Urunluneri office is that official gave him his business card and said that he may fish from shore, and if anybody (like police) is giving him trouble, give this card and let me talk to them. See, sounds like very Turkish way of doing things. Also, I am thinking, as he is Russian, and not EU, maybe you can get a license. The cost is 10 euro, or a 100 for the full year.
Like I said, this is all second hand knowledge.