Saw this mount on Facebook. Plugs into your stern light and powers the camera from the boat battery. Also elevates the camera securely to film the action in the hole boat running or fishing.
http://yolotek.com/collections/frontpage/products/aquastick-unpowered?variant=6851369793
http://yolotek.com/collections/frontpage/products/aquastick-unpowered?variant=6851369793