Should I take a 3 yr old fishing or wait untill he is older?
It is okay to take a 3 year old for fishing. You can use this time to train him accordingly or for fun. Note that you need to be extra careful so as to avoid any accident.
Give Him a hand held net and make sure he doesn't fall off. Your kid will love it if their are minos.
It really depends on the child. Some have the attention span and others might find it very boring. Try a short fishing trip to see how the child reacts.