Do you get different bugs/fish from different islands or hemispheres?

Bugs, sea creatures and fish differ from month to month. What is available in the Northern hemisphere in a month is different from Southern. There is a section of this website that shows the fish. The unofficial acnh guide is a great, and free app to help you catch all the creatu

The guide will tell you what time range, and location the different creatures are found. You can also google lists that will show you. I like the visual aspect of the app. They also give information like the shadow size of fish.