I was fishing at a lake/pond I didn't see any signs that said no fishing or anything like that so I fished. The lake had houses on it and I ...

Question

I was fishing at a lake/pond I didn't see any signs that said no fishing or anything like that so I fished. The lake had houses on it and I found a little gap thy didn't have any houses or anything close to it and an older lady approached me saying she owns the lake and that I can't fish but I continued to fish and she took my license plate number what can she do if anything she said she was going to tell the cops but I didn't do anything illegal.

Answer

On the facts you present, whether you did anything illegal depends on if she was telling the truth. If she in fact owns the lake and land and you sat on your tush and continued to fish when she told you to leave then you have likely committed at least some form of trespass possibly some form of theft if you caught and took any fish - both of which are crimes and both of which are illegal. If she got enough identifying information and wants to take the time and effort to go to the magistrate to swear out a warrant, then you are possibly going to be arrested soon.