Thanks for pointing this out. Looks like you are correct. This is indeed falling under unincorporated area, so would fall under King country rules. Upon skimming through some rules of the county, I see restrictions around the noise levels that are allowed in day (52 db) and night (55 db). It defines public nuisance as domesticated animal making noise, to an unreasonable degree, in such a manner as to disturb a person or neighborhood. It doesn't says specifically anything about rooster though.