Boots
Boots or shoes, worn for three reasons: the boat has a wet varnished surface, is rocking and you can be tossed around, so good traction is important; when the boat is launched you will be walking around at the bottom of the boat ramp, where there is over a century of rainwater runoff as well as many rocks with sharp shells; and if you do capsize you need something that is not going to restrict your ability to swim.