Cal. Fish and Game Code § 8123

(a) If any person knows that a vessel contains salmon obtained by high seas interception or that the owner or operator of the vessel intends to engage in the high seas interception of salmon, it is unlawful for that person to do any of the following: (1) Move persons, cargo, or other property to or from the vessel. (2) Service or repair the vessel or its equipment. (3) Provide the vessel with power, supplies, equipment, or fuel. (4) Provide the vessel with information, other than weather reports, capable of aiding the high seas interception of salmon or frustrating or avoiding detection, including communicating the movements, intentions, or activities of state or federal law enforcement officials or other fishing vessels. (5) Permit the vessel to dock or anchor, or to remain docked or anchored, if that person is responsible for the operation of the facility, harbor, or anchorage. (b) This section does not prohibit any person from performing any act or acts set forth in subdivision (a), if that person reasonably believes that the act or acts were necessary for humanitarian or environmental purposes or to prevent a significant loss of property, if that person provides immediate notice, by the quickest available means, to the United States Coast Guard, the department, or any law enforcement agency as to the type of assistance provided and the circumstances involved.