As used in this chapter:
(a) “Watercraft” means any boat, ship, barge, craft or floating thing designed for navigation in the water; and
(b) “Nonresident” means a person who is not a resident of this State at the time the accident or collision occurs or at the time a cause of action or claim for relief arises against him, and also means a person who, at the time the accident or collision occurs or at the time a cause of action or claim for relief arises against him is a resident of this State but subsequently becomes a nonresident of this State.