If you were ever in a survival situation where you were trying to fish to provide food for yourself and your family you would need a way to get as many fish as possible in as short a time. Off grid survival shows how to set up a multi line fishing line so you can set it up and then check every few hours. With multiple lines you would hopefully catch multiple fish. I don’t think this is legal but in a bad scenario it may just feed you.
Multiple Stream Line Fishing