fishing boat vs watercraft

fishing boat and watercraft both are nouns.

Word	Noun	Adjective	Verb	Adverb
fishing boat	Yes	No	No	No
watercraft	Yes	No	No	No

As nouns, watercraft is a hypernym of fishing boat; that is, watercraft is a word with a broader meaning than fishing boat:

fishing boat: a vessel for fishing; often has a well to keep the catch alive
watercraft: a craft designed for water transportation

Other hypernyms of fishing boat include vessel.

fishing boat (noun)	watercraft (noun)
a vessel for fishing; often has a well to keep the catch alive	a craft designed for water transportation
	skill in the management of boats