California sea lions are rare but occasionally show up in Southeast Alaska and have been documented in other parts of Alaska as well.
Emma Luck writes,
California sea lions are rare in the Juneau. This is the first time one has been spotted hauled out in the Auke Bay area.
A recent outbreak of leptospirosis has resulted in deaths of California sea lions in Oregon see article. We are interested in the health of sea lions (Stellar and California) on the Pacific Coast. If you have observations about sea lions in your area, you can post them on LEO Network. October 30, 2017.
There have been sightings in other places in Alaska as well, with records going back over a decade. In an Arctic Science Journeys article (attached) John Maniscalco of the Alaska SeaLife Center reports seeing California sea lions at Chiswell Island through remotely operated cameras. Maniscalco stated that in 2002 a growing number of California sea lions were showing up on Steller sea lion rookeries and haul-outs across the state. At the time 33 sightings had been recorded, some as far west as the Pribilof Islands in the Bering Sea. This observation has been forwarded to the Alaska Sealife Center for a consult. M. Brubaker
More information on California and Stellar Sea Lions can be found in the Animal Files species profiles.