Wearing boots and riding a boat causes your feet to appear through the boat. When you sprint in the boat, it causes sprinting particles when the boat is on water 1 block deep.
Sprinting Particles while in a Boat
Shows "sprint" particles while in a boat
While riding a unsaddled horse or a minecart and pressing the sprint keys, sprint particles are visible
Ocelots and stray cats in minecarts / boats still try and run