RCW 77.15.740
I agree that the law is aimed at recreational vessel owners.

Intent -- 2008 c 225: "The legislature encourages the state's law enforcement agencies to utilize existing statutes and regulations to protect southern resident orca whales from impacts from vessels, including the vessel operation and enforcement standards contained in chapter 79A.60 RCW." [2008 c 225 § 3.]

RCW 79A.60 heading reads REGULATION OF RECREATIONAL VESSELS.