I have no idea, Sharon, but if there are fishless coves, then you can certainly have it for your wip. By the way, when I first read this, I thought, Covers without fish? And all I could think of was the goldfish bowl with the fish jumping out--it's on two books. lol.
By the way, just because there are no fish observed does not mean there aren't any fish in that particular area. I don't know whether this helps your wip or not, but I'm throwing it out there.