California Code, Harbors and Navigation Code - HNC § 495.4

The sheriff or marshal to whom the writ is directed and delivered shall execute it without delay, and shall attach and keep in his or her custody the vessel, named therein, with its tackle, appurtenances, appliances, furnishings, and furniture, until discharged in due course of law;  but the sheriff or marshal is not authorized by any such writ to interfere with the discharge of any merchandise on board of the vessel or with the removal of any trunks or other property of passengers, or of the captain, mate, seamen, steward, cook, or other persons employed on board.