Lots of folk art fish signs are fake. I have no idea why, but I guess unscrupulous antique dealers like to "reel in" a "big catch" at some of those high-priced shows. How to tell if your tin sign is real? Uneven rust throughout...more on one side than the other. Imagine a piece of tin hanging in the elements and consider what would happen to it over the years. Reddish rust all over is often a sign of a chemical bath done at the fake folk art store. The same applies to weathervanes and such. It should look weathered.
Punta Gorda, which has weathered a few hurricanes, is HERE on Wiki, and the official website of the town is HERE
Tin Fish Sign from Punta Gorda, Florida. 40 inches long. Old. Collection Jim Linderman
Books and Ebooks by Jim Linderman are available HERE