I rode a bike a lot when I was an exchange student in Japan. Was very useful for traveling around the town. I'm planning to go back to work there and so always have in the back of my mind that I'll have to sell anything that I buy and can't take with me. Public transport is pretty good here. I can get pretty much anywhere I need with two busses and never have to wait very long. Still, I may well get a bike given current circumstances.Personally i'd forget the public transport and get a decent mtb. You can set off whenever you like, go home whenever you like etc, no waiting for sceduled transport.
A 25/30 mile radious is easy enough on a push rod with tackle and may give you plenty options.
Be warned though, you may find you ditch the fishing gear and start bikin' !