Cal. Fish & G. Code § 5504
The department may issue a letter of authorization to allow the taking of marine living resources or to authorize the take and possession of marine resources and possession of gear or equipment that would otherwise be prohibited in marine waters to support data collection, environmental cleanup, hazard removal, or public health and safety. A letter of authorization shall be valid for no more than 30 days, shall not be extended, and shall be issued only to meet immediate time-sensitive public safety, public health, research, or environmental needs, and shall not authorize the taking of fully protected species listed in Section 3511, 4700, 5050, or 5515, or species listed as threatened or endangered pursuant to Section 2070. A letter of authorization is not a substitute for a permit issued under Section 1002, Section 1022, or any other law and regulation that can otherwise be obtained. A letter of authorization shall identify the issuee and include detailed information about the activity authorized. The department shall maintain records of all letters of authorization for no less than five years from the date of issuance, and shall provide them upon request to the public.
Ca. Fish and Game Code § 5504