Beach of Scathach - underwater inhabitants

I also think that the 2 different areas give different things too. I fished in the river for quite some time, and I get things that I didn't get in the troll area. Things like jellyfish and striped marlin were pretty common in the river, but I still haven't caught a either one in the troll spot. There's also stuff in the troll spot that I haven't caught in the river too. Stuff like sunfish, but I know i caught rainbow trouts in both spots. Can anyone else check this out? I caught a bracer knuckle manual in the ocean area, and it might be an ocean thing.